1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
51 #include "hard-reg-set.h"
52 #include "insn-config.h"
55 #include "basic-block.h"
61 #include "integrate.h"
63 #ifndef TRAMPOLINE_ALIGNMENT
64 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
67 #ifndef LOCAL_ALIGNMENT
68 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
71 /* Some systems use __main in a way incompatible with its use in gcc, in these
72 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
73 give the same symbol without quotes for an alternative entry point. You
74 must define both, or neither. */
76 #define NAME__MAIN "__main"
77 #define SYMBOL__MAIN __main
80 /* Round a value to the lowest integer less than it that is a multiple of
81 the required alignment. Avoid using division in case the value is
82 negative. Assume the alignment is a power of two. */
83 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
85 /* Similar, but round to the next highest integer that meets the
87 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
89 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
90 during rtl generation. If they are different register numbers, this is
91 always true. It may also be true if
92 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
93 generation. See fix_lexical_addr for details. */
95 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
96 #define NEED_SEPARATE_AP
99 /* Nonzero if function being compiled doesn't contain any calls
100 (ignoring the prologue and epilogue). This is set prior to
101 local register allocation and is valid for the remaining
103 int current_function_is_leaf;
105 /* Nonzero if function being compiled doesn't contain any instructions
106 that can throw an exception. This is set prior to final. */
108 int current_function_nothrow;
110 /* Nonzero if function being compiled doesn't modify the stack pointer
111 (ignoring the prologue and epilogue). This is only valid after
112 life_analysis has run. */
113 int current_function_sp_is_unchanging;
115 /* Nonzero if the function being compiled is a leaf function which only
116 uses leaf registers. This is valid after reload (specifically after
117 sched2) and is useful only if the port defines LEAF_REGISTERS. */
118 int current_function_uses_only_leaf_regs;
120 /* Nonzero once virtual register instantiation has been done.
121 assign_stack_local uses frame_pointer_rtx when this is nonzero.
122 calls.c:emit_library_call_value_1 uses it to set up
123 post-instantiation libcalls. */
124 int virtuals_instantiated;
126 /* These variables hold pointers to functions to create and destroy
127 target specific, per-function data structures. */
128 void (*init_machine_status) PARAMS ((struct function *));
129 void (*free_machine_status) PARAMS ((struct function *));
130 /* This variable holds a pointer to a function to register any
131 data items in the target specific, per-function data structure
132 that will need garbage collection. */
133 void (*mark_machine_status) PARAMS ((struct function *));
135 /* Likewise, but for language-specific data. */
136 void (*init_lang_status) PARAMS ((struct function *));
137 void (*save_lang_status) PARAMS ((struct function *));
138 void (*restore_lang_status) PARAMS ((struct function *));
139 void (*mark_lang_status) PARAMS ((struct function *));
140 void (*free_lang_status) PARAMS ((struct function *));
142 /* The FUNCTION_DECL for an inline function currently being expanded. */
143 tree inline_function_decl;
145 /* The currently compiled function. */
146 struct function *cfun = 0;
148 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
149 static varray_type prologue;
150 static varray_type epilogue;
152 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
154 static varray_type sibcall_epilogue;
156 /* In order to evaluate some expressions, such as function calls returning
157 structures in memory, we need to temporarily allocate stack locations.
158 We record each allocated temporary in the following structure.
160 Associated with each temporary slot is a nesting level. When we pop up
161 one level, all temporaries associated with the previous level are freed.
162 Normally, all temporaries are freed after the execution of the statement
163 in which they were created. However, if we are inside a ({...}) grouping,
164 the result may be in a temporary and hence must be preserved. If the
165 result could be in a temporary, we preserve it if we can determine which
166 one it is in. If we cannot determine which temporary may contain the
167 result, all temporaries are preserved. A temporary is preserved by
168 pretending it was allocated at the previous nesting level.
170 Automatic variables are also assigned temporary slots, at the nesting
171 level where they are defined. They are marked a "kept" so that
172 free_temp_slots will not free them. */
176 /* Points to next temporary slot. */
177 struct temp_slot *next;
178 /* The rtx to used to reference the slot. */
180 /* The rtx used to represent the address if not the address of the
181 slot above. May be an EXPR_LIST if multiple addresses exist. */
183 /* The alignment (in bits) of the slot. */
185 /* The size, in units, of the slot. */
187 /* The type of the object in the slot, or zero if it doesn't correspond
188 to a type. We use this to determine whether a slot can be reused.
189 It can be reused if objects of the type of the new slot will always
190 conflict with objects of the type of the old slot. */
192 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
194 /* Non-zero if this temporary is currently in use. */
196 /* Non-zero if this temporary has its address taken. */
198 /* Nesting level at which this slot is being used. */
200 /* Non-zero if this should survive a call to free_temp_slots. */
202 /* The offset of the slot from the frame_pointer, including extra space
203 for alignment. This info is for combine_temp_slots. */
204 HOST_WIDE_INT base_offset;
205 /* The size of the slot, including extra space for alignment. This
206 info is for combine_temp_slots. */
207 HOST_WIDE_INT full_size;
210 /* This structure is used to record MEMs or pseudos used to replace VAR, any
211 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
212 maintain this list in case two operands of an insn were required to match;
213 in that case we must ensure we use the same replacement. */
215 struct fixup_replacement
219 struct fixup_replacement *next;
222 struct insns_for_mem_entry
224 /* The KEY in HE will be a MEM. */
225 struct hash_entry he;
226 /* These are the INSNS which reference the MEM. */
230 /* Forward declarations. */
232 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
233 int, struct function *));
234 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
235 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
236 enum machine_mode, enum machine_mode,
237 int, unsigned int, int,
238 struct hash_table *));
239 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
241 struct hash_table *));
242 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
243 struct hash_table *));
244 static struct fixup_replacement
245 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
246 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
248 static void fixup_var_refs_insns_with_hash
249 PARAMS ((struct hash_table *, rtx,
250 enum machine_mode, int, rtx));
251 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
253 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
254 struct fixup_replacement **, rtx));
255 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
256 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
257 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
258 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
259 static void instantiate_decls PARAMS ((tree, int));
260 static void instantiate_decls_1 PARAMS ((tree, int));
261 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
262 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
263 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
264 static void delete_handlers PARAMS ((void));
265 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
266 struct args_size *));
267 #ifndef ARGS_GROW_DOWNWARD
268 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
271 static rtx round_trampoline_addr PARAMS ((rtx));
272 static rtx adjust_trampoline_addr PARAMS ((rtx));
273 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
274 static void reorder_blocks_0 PARAMS ((tree));
275 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
276 static void reorder_fix_fragments PARAMS ((tree));
277 static tree blocks_nreverse PARAMS ((tree));
278 static int all_blocks PARAMS ((tree, tree *));
279 static tree *get_block_vector PARAMS ((tree, int *));
280 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
281 /* We always define `record_insns' even if its not used so that we
282 can always export `prologue_epilogue_contains'. */
283 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
284 static int contains PARAMS ((rtx, varray_type));
286 static void emit_return_into_block PARAMS ((basic_block, rtx));
288 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
289 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
290 struct hash_table *));
291 static void purge_single_hard_subreg_set PARAMS ((rtx));
292 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
293 static rtx keep_stack_depressed PARAMS ((rtx));
295 static int is_addressof PARAMS ((rtx *, void *));
296 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
299 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
300 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
301 static int insns_for_mem_walk PARAMS ((rtx *, void *));
302 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
303 static void mark_function_status PARAMS ((struct function *));
304 static void maybe_mark_struct_function PARAMS ((void *));
305 static void prepare_function_start PARAMS ((void));
306 static void do_clobber_return_reg PARAMS ((rtx, void *));
307 static void do_use_return_reg PARAMS ((rtx, void *));
309 /* Pointer to chain of `struct function' for containing functions. */
310 static struct function *outer_function_chain;
312 /* Given a function decl for a containing function,
313 return the `struct function' for it. */
316 find_function_data (decl)
321 for (p = outer_function_chain; p; p = p->outer)
328 /* Save the current context for compilation of a nested function.
329 This is called from language-specific code. The caller should use
330 the save_lang_status callback to save any language-specific state,
331 since this function knows only about language-independent
335 push_function_context_to (context)
342 if (context == current_function_decl)
343 cfun->contains_functions = 1;
346 struct function *containing = find_function_data (context);
347 containing->contains_functions = 1;
352 init_dummy_function_start ();
355 p->outer = outer_function_chain;
356 outer_function_chain = p;
357 p->fixup_var_refs_queue = 0;
359 if (save_lang_status)
360 (*save_lang_status) (p);
366 push_function_context ()
368 push_function_context_to (current_function_decl);
371 /* Restore the last saved context, at the end of a nested function.
372 This function is called from language-specific code. */
375 pop_function_context_from (context)
376 tree context ATTRIBUTE_UNUSED;
378 struct function *p = outer_function_chain;
379 struct var_refs_queue *queue;
382 outer_function_chain = p->outer;
384 current_function_decl = p->decl;
387 restore_emit_status (p);
389 if (restore_lang_status)
390 (*restore_lang_status) (p);
392 /* Finish doing put_var_into_stack for any of our variables which became
393 addressable during the nested function. If only one entry has to be
394 fixed up, just do that one. Otherwise, first make a list of MEMs that
395 are not to be unshared. */
396 if (p->fixup_var_refs_queue == 0)
398 else if (p->fixup_var_refs_queue->next == 0)
399 fixup_var_refs (p->fixup_var_refs_queue->modified,
400 p->fixup_var_refs_queue->promoted_mode,
401 p->fixup_var_refs_queue->unsignedp,
402 p->fixup_var_refs_queue->modified, 0);
407 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
408 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
410 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
411 fixup_var_refs (queue->modified, queue->promoted_mode,
412 queue->unsignedp, list, 0);
416 p->fixup_var_refs_queue = 0;
418 /* Reset variables that have known state during rtx generation. */
419 rtx_equal_function_value_matters = 1;
420 virtuals_instantiated = 0;
421 generating_concat_p = 1;
425 pop_function_context ()
427 pop_function_context_from (current_function_decl);
430 /* Clear out all parts of the state in F that can safely be discarded
431 after the function has been parsed, but not compiled, to let
432 garbage collection reclaim the memory. */
435 free_after_parsing (f)
438 /* f->expr->forced_labels is used by code generation. */
439 /* f->emit->regno_reg_rtx is used by code generation. */
440 /* f->varasm is used by code generation. */
441 /* f->eh->eh_return_stub_label is used by code generation. */
443 if (free_lang_status)
444 (*free_lang_status) (f);
445 free_stmt_status (f);
448 /* Clear out all parts of the state in F that can safely be discarded
449 after the function has been compiled, to let garbage collection
450 reclaim the memory. */
453 free_after_compilation (f)
457 free_expr_status (f);
458 free_emit_status (f);
459 free_varasm_status (f);
461 if (free_machine_status)
462 (*free_machine_status) (f);
464 if (f->x_parm_reg_stack_loc)
465 free (f->x_parm_reg_stack_loc);
467 f->x_temp_slots = NULL;
468 f->arg_offset_rtx = NULL;
469 f->return_rtx = NULL;
470 f->internal_arg_pointer = NULL;
471 f->x_nonlocal_labels = NULL;
472 f->x_nonlocal_goto_handler_slots = NULL;
473 f->x_nonlocal_goto_handler_labels = NULL;
474 f->x_nonlocal_goto_stack_level = NULL;
475 f->x_cleanup_label = NULL;
476 f->x_return_label = NULL;
477 f->x_save_expr_regs = NULL;
478 f->x_stack_slot_list = NULL;
479 f->x_rtl_expr_chain = NULL;
480 f->x_tail_recursion_label = NULL;
481 f->x_tail_recursion_reentry = NULL;
482 f->x_arg_pointer_save_area = NULL;
483 f->x_clobber_return_insn = NULL;
484 f->x_context_display = NULL;
485 f->x_trampoline_list = NULL;
486 f->x_parm_birth_insn = NULL;
487 f->x_last_parm_insn = NULL;
488 f->x_parm_reg_stack_loc = NULL;
489 f->fixup_var_refs_queue = NULL;
490 f->original_arg_vector = NULL;
491 f->original_decl_initial = NULL;
492 f->inl_last_parm_insn = NULL;
493 f->epilogue_delay_list = NULL;
496 /* Allocate fixed slots in the stack frame of the current function. */
498 /* Return size needed for stack frame based on slots so far allocated in
500 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
501 the caller may have to do that. */
504 get_func_frame_size (f)
507 #ifdef FRAME_GROWS_DOWNWARD
508 return -f->x_frame_offset;
510 return f->x_frame_offset;
514 /* Return size needed for stack frame based on slots so far allocated.
515 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
516 the caller may have to do that. */
520 return get_func_frame_size (cfun);
523 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
524 with machine mode MODE.
526 ALIGN controls the amount of alignment for the address of the slot:
527 0 means according to MODE,
528 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
529 positive specifies alignment boundary in bits.
531 We do not round to stack_boundary here.
533 FUNCTION specifies the function to allocate in. */
536 assign_stack_local_1 (mode, size, align, function)
537 enum machine_mode mode;
540 struct function *function;
543 int bigend_correction = 0;
545 int frame_off, frame_alignment, frame_phase;
552 alignment = BIGGEST_ALIGNMENT;
554 alignment = GET_MODE_ALIGNMENT (mode);
556 /* Allow the target to (possibly) increase the alignment of this
558 type = type_for_mode (mode, 0);
560 alignment = LOCAL_ALIGNMENT (type, alignment);
562 alignment /= BITS_PER_UNIT;
564 else if (align == -1)
566 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
567 size = CEIL_ROUND (size, alignment);
570 alignment = align / BITS_PER_UNIT;
572 #ifdef FRAME_GROWS_DOWNWARD
573 function->x_frame_offset -= size;
576 /* Ignore alignment we can't do with expected alignment of the boundary. */
577 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
578 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
580 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
581 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
583 /* Calculate how many bytes the start of local variables is off from
585 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
586 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
587 frame_phase = frame_off ? frame_alignment - frame_off : 0;
589 /* Round frame offset to that alignment.
590 We must be careful here, since FRAME_OFFSET might be negative and
591 division with a negative dividend isn't as well defined as we might
592 like. So we instead assume that ALIGNMENT is a power of two and
593 use logical operations which are unambiguous. */
594 #ifdef FRAME_GROWS_DOWNWARD
595 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
597 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
600 /* On a big-endian machine, if we are allocating more space than we will use,
601 use the least significant bytes of those that are allocated. */
602 if (BYTES_BIG_ENDIAN && mode != BLKmode)
603 bigend_correction = size - GET_MODE_SIZE (mode);
605 /* If we have already instantiated virtual registers, return the actual
606 address relative to the frame pointer. */
607 if (function == cfun && virtuals_instantiated)
608 addr = plus_constant (frame_pointer_rtx,
609 (frame_offset + bigend_correction
610 + STARTING_FRAME_OFFSET));
612 addr = plus_constant (virtual_stack_vars_rtx,
613 function->x_frame_offset + bigend_correction);
615 #ifndef FRAME_GROWS_DOWNWARD
616 function->x_frame_offset += size;
619 x = gen_rtx_MEM (mode, addr);
621 function->x_stack_slot_list
622 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
627 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
631 assign_stack_local (mode, size, align)
632 enum machine_mode mode;
636 return assign_stack_local_1 (mode, size, align, cfun);
639 /* Allocate a temporary stack slot and record it for possible later
642 MODE is the machine mode to be given to the returned rtx.
644 SIZE is the size in units of the space required. We do no rounding here
645 since assign_stack_local will do any required rounding.
647 KEEP is 1 if this slot is to be retained after a call to
648 free_temp_slots. Automatic variables for a block are allocated
649 with this flag. KEEP is 2 if we allocate a longer term temporary,
650 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
651 if we are to allocate something at an inner level to be treated as
652 a variable in the block (e.g., a SAVE_EXPR).
654 TYPE is the type that will be used for the stack slot. */
657 assign_stack_temp_for_type (mode, size, keep, type)
658 enum machine_mode mode;
664 struct temp_slot *p, *best_p = 0;
666 /* If SIZE is -1 it means that somebody tried to allocate a temporary
667 of a variable size. */
672 align = BIGGEST_ALIGNMENT;
674 align = GET_MODE_ALIGNMENT (mode);
677 type = type_for_mode (mode, 0);
680 align = LOCAL_ALIGNMENT (type, align);
682 /* Try to find an available, already-allocated temporary of the proper
683 mode which meets the size and alignment requirements. Choose the
684 smallest one with the closest alignment. */
685 for (p = temp_slots; p; p = p->next)
686 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
688 && objects_must_conflict_p (p->type, type)
689 && (best_p == 0 || best_p->size > p->size
690 || (best_p->size == p->size && best_p->align > p->align)))
692 if (p->align == align && p->size == size)
700 /* Make our best, if any, the one to use. */
703 /* If there are enough aligned bytes left over, make them into a new
704 temp_slot so that the extra bytes don't get wasted. Do this only
705 for BLKmode slots, so that we can be sure of the alignment. */
706 if (GET_MODE (best_p->slot) == BLKmode)
708 int alignment = best_p->align / BITS_PER_UNIT;
709 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
711 if (best_p->size - rounded_size >= alignment)
713 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
714 p->in_use = p->addr_taken = 0;
715 p->size = best_p->size - rounded_size;
716 p->base_offset = best_p->base_offset + rounded_size;
717 p->full_size = best_p->full_size - rounded_size;
718 p->slot = gen_rtx_MEM (BLKmode,
719 plus_constant (XEXP (best_p->slot, 0),
721 p->align = best_p->align;
724 p->type = best_p->type;
725 p->next = temp_slots;
728 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
731 best_p->size = rounded_size;
732 best_p->full_size = rounded_size;
739 /* If we still didn't find one, make a new temporary. */
742 HOST_WIDE_INT frame_offset_old = frame_offset;
744 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
746 /* We are passing an explicit alignment request to assign_stack_local.
747 One side effect of that is assign_stack_local will not round SIZE
748 to ensure the frame offset remains suitably aligned.
750 So for requests which depended on the rounding of SIZE, we go ahead
751 and round it now. We also make sure ALIGNMENT is at least
752 BIGGEST_ALIGNMENT. */
753 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
755 p->slot = assign_stack_local (mode,
757 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
763 /* The following slot size computation is necessary because we don't
764 know the actual size of the temporary slot until assign_stack_local
765 has performed all the frame alignment and size rounding for the
766 requested temporary. Note that extra space added for alignment
767 can be either above or below this stack slot depending on which
768 way the frame grows. We include the extra space if and only if it
769 is above this slot. */
770 #ifdef FRAME_GROWS_DOWNWARD
771 p->size = frame_offset_old - frame_offset;
776 /* Now define the fields used by combine_temp_slots. */
777 #ifdef FRAME_GROWS_DOWNWARD
778 p->base_offset = frame_offset;
779 p->full_size = frame_offset_old - frame_offset;
781 p->base_offset = frame_offset_old;
782 p->full_size = frame_offset - frame_offset_old;
785 p->next = temp_slots;
791 p->rtl_expr = seq_rtl_expr;
796 p->level = target_temp_slot_level;
801 p->level = var_temp_slot_level;
806 p->level = temp_slot_level;
810 /* We may be reusing an old slot, so clear any MEM flags that may have been
812 RTX_UNCHANGING_P (p->slot) = 0;
813 MEM_IN_STRUCT_P (p->slot) = 0;
814 MEM_SCALAR_P (p->slot) = 0;
815 MEM_VOLATILE_P (p->slot) = 0;
816 set_mem_alias_set (p->slot, 0);
818 /* If we know the alias set for the memory that will be used, use
819 it. If there's no TYPE, then we don't know anything about the
820 alias set for the memory. */
821 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
822 set_mem_align (p->slot, align);
824 /* If a type is specified, set the relevant flags. */
827 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
828 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
829 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
835 /* Allocate a temporary stack slot and record it for possible later
836 reuse. First three arguments are same as in preceding function. */
839 assign_stack_temp (mode, size, keep)
840 enum machine_mode mode;
844 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
847 /* Assign a temporary of given TYPE.
848 KEEP is as for assign_stack_temp.
849 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
850 it is 0 if a register is OK.
851 DONT_PROMOTE is 1 if we should not promote values in register
855 assign_temp (type, keep, memory_required, dont_promote)
859 int dont_promote ATTRIBUTE_UNUSED;
861 enum machine_mode mode = TYPE_MODE (type);
862 #ifndef PROMOTE_FOR_CALL_ONLY
863 int unsignedp = TREE_UNSIGNED (type);
866 if (mode == BLKmode || memory_required)
868 HOST_WIDE_INT size = int_size_in_bytes (type);
871 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
872 problems with allocating the stack space. */
876 /* Unfortunately, we don't yet know how to allocate variable-sized
877 temporaries. However, sometimes we have a fixed upper limit on
878 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
879 instead. This is the case for Chill variable-sized strings. */
880 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
881 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
882 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
883 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
885 tmp = assign_stack_temp_for_type (mode, size, keep, type);
889 #ifndef PROMOTE_FOR_CALL_ONLY
891 mode = promote_mode (type, mode, &unsignedp, 0);
894 return gen_reg_rtx (mode);
897 /* Combine temporary stack slots which are adjacent on the stack.
899 This allows for better use of already allocated stack space. This is only
900 done for BLKmode slots because we can be sure that we won't have alignment
901 problems in this case. */
904 combine_temp_slots ()
906 struct temp_slot *p, *q;
907 struct temp_slot *prev_p, *prev_q;
910 /* We can't combine slots, because the information about which slot
911 is in which alias set will be lost. */
912 if (flag_strict_aliasing)
915 /* If there are a lot of temp slots, don't do anything unless
916 high levels of optimization. */
917 if (! flag_expensive_optimizations)
918 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
919 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
922 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
926 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
927 for (q = p->next, prev_q = p; q; q = prev_q->next)
930 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
932 if (p->base_offset + p->full_size == q->base_offset)
934 /* Q comes after P; combine Q into P. */
936 p->full_size += q->full_size;
939 else if (q->base_offset + q->full_size == p->base_offset)
941 /* P comes after Q; combine P into Q. */
943 q->full_size += p->full_size;
948 /* Either delete Q or advance past it. */
950 prev_q->next = q->next;
954 /* Either delete P or advance past it. */
958 prev_p->next = p->next;
960 temp_slots = p->next;
967 /* Find the temp slot corresponding to the object at address X. */
969 static struct temp_slot *
970 find_temp_slot_from_address (x)
976 for (p = temp_slots; p; p = p->next)
981 else if (XEXP (p->slot, 0) == x
983 || (GET_CODE (x) == PLUS
984 && XEXP (x, 0) == virtual_stack_vars_rtx
985 && GET_CODE (XEXP (x, 1)) == CONST_INT
986 && INTVAL (XEXP (x, 1)) >= p->base_offset
987 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
990 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
991 for (next = p->address; next; next = XEXP (next, 1))
992 if (XEXP (next, 0) == x)
996 /* If we have a sum involving a register, see if it points to a temp
998 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
999 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1001 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1002 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1008 /* Indicate that NEW is an alternate way of referring to the temp slot
1009 that previously was known by OLD. */
1012 update_temp_slot_address (old, new)
1015 struct temp_slot *p;
1017 if (rtx_equal_p (old, new))
1020 p = find_temp_slot_from_address (old);
1022 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1023 is a register, see if one operand of the PLUS is a temporary
1024 location. If so, NEW points into it. Otherwise, if both OLD and
1025 NEW are a PLUS and if there is a register in common between them.
1026 If so, try a recursive call on those values. */
1029 if (GET_CODE (old) != PLUS)
1032 if (GET_CODE (new) == REG)
1034 update_temp_slot_address (XEXP (old, 0), new);
1035 update_temp_slot_address (XEXP (old, 1), new);
1038 else if (GET_CODE (new) != PLUS)
1041 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1042 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1043 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1044 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1045 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1046 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1047 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1048 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1053 /* Otherwise add an alias for the temp's address. */
1054 else if (p->address == 0)
1058 if (GET_CODE (p->address) != EXPR_LIST)
1059 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1061 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1065 /* If X could be a reference to a temporary slot, mark the fact that its
1066 address was taken. */
1069 mark_temp_addr_taken (x)
1072 struct temp_slot *p;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1082 p = find_temp_slot_from_address (XEXP (x, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (x)
1100 struct temp_slot *p = 0;
1102 /* If there is no result, we still might have some objects whose address
1103 were taken, so we need to make sure they stay around. */
1106 for (p = temp_slots; p; p = p->next)
1107 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1113 /* If X is a register that is being used as a pointer, see if we have
1114 a temporary slot we know it points to. To be consistent with
1115 the code below, we really should preserve all non-kept slots
1116 if we can't find a match, but that seems to be much too costly. */
1117 if (GET_CODE (x) == REG && REG_POINTER (x))
1118 p = find_temp_slot_from_address (x);
1120 /* If X is not in memory or is at a constant address, it cannot be in
1121 a temporary slot, but it can contain something whose address was
1123 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1125 for (p = temp_slots; p; p = p->next)
1126 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1132 /* First see if we can find a match. */
1134 p = find_temp_slot_from_address (XEXP (x, 0));
1138 /* Move everything at our level whose address was taken to our new
1139 level in case we used its address. */
1140 struct temp_slot *q;
1142 if (p->level == temp_slot_level)
1144 for (q = temp_slots; q; q = q->next)
1145 if (q != p && q->addr_taken && q->level == p->level)
1154 /* Otherwise, preserve all non-kept slots at this level. */
1155 for (p = temp_slots; p; p = p->next)
1156 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1160 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1161 with that RTL_EXPR, promote it into a temporary slot at the present
1162 level so it will not be freed when we free slots made in the
1166 preserve_rtl_expr_result (x)
1169 struct temp_slot *p;
1171 /* If X is not in memory or is at a constant address, it cannot be in
1172 a temporary slot. */
1173 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1176 /* If we can find a match, move it to our level unless it is already at
1178 p = find_temp_slot_from_address (XEXP (x, 0));
1181 p->level = MIN (p->level, temp_slot_level);
1188 /* Free all temporaries used so far. This is normally called at the end
1189 of generating code for a statement. Don't free any temporaries
1190 currently in use for an RTL_EXPR that hasn't yet been emitted.
1191 We could eventually do better than this since it can be reused while
1192 generating the same RTL_EXPR, but this is complex and probably not
1198 struct temp_slot *p;
1200 for (p = temp_slots; p; p = p->next)
1201 if (p->in_use && p->level == temp_slot_level && ! p->keep
1202 && p->rtl_expr == 0)
1205 combine_temp_slots ();
1208 /* Free all temporary slots used in T, an RTL_EXPR node. */
1211 free_temps_for_rtl_expr (t)
1214 struct temp_slot *p;
1216 for (p = temp_slots; p; p = p->next)
1217 if (p->rtl_expr == t)
1219 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1220 needs to be preserved. This can happen if a temporary in
1221 the RTL_EXPR was addressed; preserve_temp_slots will move
1222 the temporary into a higher level. */
1223 if (temp_slot_level <= p->level)
1226 p->rtl_expr = NULL_TREE;
1229 combine_temp_slots ();
1232 /* Mark all temporaries ever allocated in this function as not suitable
1233 for reuse until the current level is exited. */
1236 mark_all_temps_used ()
1238 struct temp_slot *p;
1240 for (p = temp_slots; p; p = p->next)
1242 p->in_use = p->keep = 1;
1243 p->level = MIN (p->level, temp_slot_level);
1247 /* Push deeper into the nesting level for stack temporaries. */
1255 /* Likewise, but save the new level as the place to allocate variables
1260 push_temp_slots_for_block ()
1264 var_temp_slot_level = temp_slot_level;
1267 /* Likewise, but save the new level as the place to allocate temporaries
1268 for TARGET_EXPRs. */
1271 push_temp_slots_for_target ()
1275 target_temp_slot_level = temp_slot_level;
1278 /* Set and get the value of target_temp_slot_level. The only
1279 permitted use of these functions is to save and restore this value. */
1282 get_target_temp_slot_level ()
1284 return target_temp_slot_level;
1288 set_target_temp_slot_level (level)
1291 target_temp_slot_level = level;
1295 /* Pop a temporary nesting level. All slots in use in the current level
1301 struct temp_slot *p;
1303 for (p = temp_slots; p; p = p->next)
1304 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1307 combine_temp_slots ();
1312 /* Initialize temporary slots. */
1317 /* We have not allocated any temporaries yet. */
1319 temp_slot_level = 0;
1320 var_temp_slot_level = 0;
1321 target_temp_slot_level = 0;
1324 /* Retroactively move an auto variable from a register to a stack slot.
1325 This is done when an address-reference to the variable is seen. */
1328 put_var_into_stack (decl)
1332 enum machine_mode promoted_mode, decl_mode;
1333 struct function *function = 0;
1335 int can_use_addressof;
1336 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1337 int usedp = (TREE_USED (decl)
1338 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1340 context = decl_function_context (decl);
1342 /* Get the current rtl used for this object and its original mode. */
1343 reg = (TREE_CODE (decl) == SAVE_EXPR
1344 ? SAVE_EXPR_RTL (decl)
1345 : DECL_RTL_IF_SET (decl));
1347 /* No need to do anything if decl has no rtx yet
1348 since in that case caller is setting TREE_ADDRESSABLE
1349 and a stack slot will be assigned when the rtl is made. */
1353 /* Get the declared mode for this object. */
1354 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1355 : DECL_MODE (decl));
1356 /* Get the mode it's actually stored in. */
1357 promoted_mode = GET_MODE (reg);
1359 /* If this variable comes from an outer function, find that
1360 function's saved context. Don't use find_function_data here,
1361 because it might not be in any active function.
1362 FIXME: Is that really supposed to happen?
1363 It does in ObjC at least. */
1364 if (context != current_function_decl && context != inline_function_decl)
1365 for (function = outer_function_chain; function; function = function->outer)
1366 if (function->decl == context)
1369 /* If this is a variable-size object with a pseudo to address it,
1370 put that pseudo into the stack, if the var is nonlocal. */
1371 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1372 && GET_CODE (reg) == MEM
1373 && GET_CODE (XEXP (reg, 0)) == REG
1374 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1376 reg = XEXP (reg, 0);
1377 decl_mode = promoted_mode = GET_MODE (reg);
1383 /* FIXME make it work for promoted modes too */
1384 && decl_mode == promoted_mode
1385 #ifdef NON_SAVING_SETJMP
1386 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1390 /* If we can't use ADDRESSOF, make sure we see through one we already
1392 if (! can_use_addressof && GET_CODE (reg) == MEM
1393 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1394 reg = XEXP (XEXP (reg, 0), 0);
1396 /* Now we should have a value that resides in one or more pseudo regs. */
1398 if (GET_CODE (reg) == REG)
1400 /* If this variable lives in the current function and we don't need
1401 to put things in the stack for the sake of setjmp, try to keep it
1402 in a register until we know we actually need the address. */
1403 if (can_use_addressof)
1404 gen_mem_addressof (reg, decl);
1406 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1407 decl_mode, volatilep, 0, usedp, 0);
1409 else if (GET_CODE (reg) == CONCAT)
1411 /* A CONCAT contains two pseudos; put them both in the stack.
1412 We do it so they end up consecutive.
1413 We fixup references to the parts only after we fixup references
1414 to the whole CONCAT, lest we do double fixups for the latter
1416 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1417 tree part_type = type_for_mode (part_mode, 0);
1418 rtx lopart = XEXP (reg, 0);
1419 rtx hipart = XEXP (reg, 1);
1420 #ifdef FRAME_GROWS_DOWNWARD
1421 /* Since part 0 should have a lower address, do it second. */
1422 put_reg_into_stack (function, hipart, part_type, part_mode,
1423 part_mode, volatilep, 0, 0, 0);
1424 put_reg_into_stack (function, lopart, part_type, part_mode,
1425 part_mode, volatilep, 0, 0, 0);
1427 put_reg_into_stack (function, lopart, part_type, part_mode,
1428 part_mode, volatilep, 0, 0, 0);
1429 put_reg_into_stack (function, hipart, part_type, part_mode,
1430 part_mode, volatilep, 0, 0, 0);
1433 /* Change the CONCAT into a combined MEM for both parts. */
1434 PUT_CODE (reg, MEM);
1435 MEM_ATTRS (reg) = 0;
1437 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1438 already computed alias sets. Here we want to re-generate. */
1440 SET_DECL_RTL (decl, NULL);
1441 set_mem_attributes (reg, decl, 1);
1443 SET_DECL_RTL (decl, reg);
1445 /* The two parts are in memory order already.
1446 Use the lower parts address as ours. */
1447 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1448 /* Prevent sharing of rtl that might lose. */
1449 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1450 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1453 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1455 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1456 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1463 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1464 into the stack frame of FUNCTION (0 means the current function).
1465 DECL_MODE is the machine mode of the user-level data type.
1466 PROMOTED_MODE is the machine mode of the register.
1467 VOLATILE_P is nonzero if this is for a "volatile" decl.
1468 USED_P is nonzero if this reg might have already been used in an insn. */
1471 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1472 original_regno, used_p, ht)
1473 struct function *function;
1476 enum machine_mode promoted_mode, decl_mode;
1478 unsigned int original_regno;
1480 struct hash_table *ht;
1482 struct function *func = function ? function : cfun;
1484 unsigned int regno = original_regno;
1487 regno = REGNO (reg);
1489 if (regno < func->x_max_parm_reg)
1490 new = func->x_parm_reg_stack_loc[regno];
1493 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1495 PUT_CODE (reg, MEM);
1496 PUT_MODE (reg, decl_mode);
1497 XEXP (reg, 0) = XEXP (new, 0);
1498 MEM_ATTRS (reg) = 0;
1499 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1500 MEM_VOLATILE_P (reg) = volatile_p;
1502 /* If this is a memory ref that contains aggregate components,
1503 mark it as such for cse and loop optimize. If we are reusing a
1504 previously generated stack slot, then we need to copy the bit in
1505 case it was set for other reasons. For instance, it is set for
1506 __builtin_va_alist. */
1509 MEM_SET_IN_STRUCT_P (reg,
1510 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1511 set_mem_alias_set (reg, get_alias_set (type));
1515 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1518 /* Make sure that all refs to the variable, previously made
1519 when it was a register, are fixed up to be valid again.
1520 See function above for meaning of arguments. */
1523 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1524 struct function *function;
1527 enum machine_mode promoted_mode;
1528 struct hash_table *ht;
1530 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1534 struct var_refs_queue *temp;
1537 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1538 temp->modified = reg;
1539 temp->promoted_mode = promoted_mode;
1540 temp->unsignedp = unsigned_p;
1541 temp->next = function->fixup_var_refs_queue;
1542 function->fixup_var_refs_queue = temp;
1545 /* Variable is local; fix it up now. */
1546 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1550 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1552 enum machine_mode promoted_mode;
1554 struct hash_table *ht;
1558 rtx first_insn = get_insns ();
1559 struct sequence_stack *stack = seq_stack;
1560 tree rtl_exps = rtl_expr_chain;
1562 /* If there's a hash table, it must record all uses of VAR. */
1567 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1572 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1573 stack == 0, may_share);
1575 /* Scan all pending sequences too. */
1576 for (; stack; stack = stack->next)
1578 push_to_full_sequence (stack->first, stack->last);
1579 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1580 stack->next != 0, may_share);
1581 /* Update remembered end of sequence
1582 in case we added an insn at the end. */
1583 stack->last = get_last_insn ();
1587 /* Scan all waiting RTL_EXPRs too. */
1588 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1590 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1591 if (seq != const0_rtx && seq != 0)
1593 push_to_sequence (seq);
1594 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1601 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1602 some part of an insn. Return a struct fixup_replacement whose OLD
1603 value is equal to X. Allocate a new structure if no such entry exists. */
1605 static struct fixup_replacement *
1606 find_fixup_replacement (replacements, x)
1607 struct fixup_replacement **replacements;
1610 struct fixup_replacement *p;
1612 /* See if we have already replaced this. */
1613 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1618 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1621 p->next = *replacements;
1628 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1629 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1630 for the current function. MAY_SHARE is either a MEM that is not
1631 to be unshared or a list of them. */
1634 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1637 enum machine_mode promoted_mode;
1644 /* fixup_var_refs_insn might modify insn, so save its next
1646 rtx next = NEXT_INSN (insn);
1648 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1649 the three sequences they (potentially) contain, and process
1650 them recursively. The CALL_INSN itself is not interesting. */
1652 if (GET_CODE (insn) == CALL_INSN
1653 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1657 /* Look at the Normal call, sibling call and tail recursion
1658 sequences attached to the CALL_PLACEHOLDER. */
1659 for (i = 0; i < 3; i++)
1661 rtx seq = XEXP (PATTERN (insn), i);
1664 push_to_sequence (seq);
1665 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1667 XEXP (PATTERN (insn), i) = get_insns ();
1673 else if (INSN_P (insn))
1674 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1681 /* Look up the insns which reference VAR in HT and fix them up. Other
1682 arguments are the same as fixup_var_refs_insns.
1684 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1685 because the hash table will point straight to the interesting insn
1686 (inside the CALL_PLACEHOLDER). */
1689 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1690 struct hash_table *ht;
1692 enum machine_mode promoted_mode;
1696 struct insns_for_mem_entry *ime
1697 = (struct insns_for_mem_entry *) hash_lookup (ht, var,
1698 /*create=*/0, /*copy=*/0);
1701 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1702 if (INSN_P (XEXP (insn_list, 0)))
1703 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1704 unsignedp, 1, may_share);
1708 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1709 the insn under examination, VAR is the variable to fix up
1710 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1711 TOPLEVEL is nonzero if this is the main insn chain for this
1715 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1718 enum machine_mode promoted_mode;
1724 rtx set, prev, prev_set;
1727 /* Remember the notes in case we delete the insn. */
1728 note = REG_NOTES (insn);
1730 /* If this is a CLOBBER of VAR, delete it.
1732 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1733 and REG_RETVAL notes too. */
1734 if (GET_CODE (PATTERN (insn)) == CLOBBER
1735 && (XEXP (PATTERN (insn), 0) == var
1736 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1737 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1738 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1740 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1741 /* The REG_LIBCALL note will go away since we are going to
1742 turn INSN into a NOTE, so just delete the
1743 corresponding REG_RETVAL note. */
1744 remove_note (XEXP (note, 0),
1745 find_reg_note (XEXP (note, 0), REG_RETVAL,
1751 /* The insn to load VAR from a home in the arglist
1752 is now a no-op. When we see it, just delete it.
1753 Similarly if this is storing VAR from a register from which
1754 it was loaded in the previous insn. This will occur
1755 when an ADDRESSOF was made for an arglist slot. */
1757 && (set = single_set (insn)) != 0
1758 && SET_DEST (set) == var
1759 /* If this represents the result of an insn group,
1760 don't delete the insn. */
1761 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1762 && (rtx_equal_p (SET_SRC (set), var)
1763 || (GET_CODE (SET_SRC (set)) == REG
1764 && (prev = prev_nonnote_insn (insn)) != 0
1765 && (prev_set = single_set (prev)) != 0
1766 && SET_DEST (prev_set) == SET_SRC (set)
1767 && rtx_equal_p (SET_SRC (prev_set), var))))
1773 struct fixup_replacement *replacements = 0;
1774 rtx next_insn = NEXT_INSN (insn);
1776 if (SMALL_REGISTER_CLASSES)
1778 /* If the insn that copies the results of a CALL_INSN
1779 into a pseudo now references VAR, we have to use an
1780 intermediate pseudo since we want the life of the
1781 return value register to be only a single insn.
1783 If we don't use an intermediate pseudo, such things as
1784 address computations to make the address of VAR valid
1785 if it is not can be placed between the CALL_INSN and INSN.
1787 To make sure this doesn't happen, we record the destination
1788 of the CALL_INSN and see if the next insn uses both that
1791 if (call_dest != 0 && GET_CODE (insn) == INSN
1792 && reg_mentioned_p (var, PATTERN (insn))
1793 && reg_mentioned_p (call_dest, PATTERN (insn)))
1795 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1797 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1799 PATTERN (insn) = replace_rtx (PATTERN (insn),
1803 if (GET_CODE (insn) == CALL_INSN
1804 && GET_CODE (PATTERN (insn)) == SET)
1805 call_dest = SET_DEST (PATTERN (insn));
1806 else if (GET_CODE (insn) == CALL_INSN
1807 && GET_CODE (PATTERN (insn)) == PARALLEL
1808 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1809 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1814 /* See if we have to do anything to INSN now that VAR is in
1815 memory. If it needs to be loaded into a pseudo, use a single
1816 pseudo for the entire insn in case there is a MATCH_DUP
1817 between two operands. We pass a pointer to the head of
1818 a list of struct fixup_replacements. If fixup_var_refs_1
1819 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1820 it will record them in this list.
1822 If it allocated a pseudo for any replacement, we copy into
1825 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1826 &replacements, no_share);
1828 /* If this is last_parm_insn, and any instructions were output
1829 after it to fix it up, then we must set last_parm_insn to
1830 the last such instruction emitted. */
1831 if (insn == last_parm_insn)
1832 last_parm_insn = PREV_INSN (next_insn);
1834 while (replacements)
1836 struct fixup_replacement *next;
1838 if (GET_CODE (replacements->new) == REG)
1843 /* OLD might be a (subreg (mem)). */
1844 if (GET_CODE (replacements->old) == SUBREG)
1846 = fixup_memory_subreg (replacements->old, insn, 0);
1849 = fixup_stack_1 (replacements->old, insn);
1851 insert_before = insn;
1853 /* If we are changing the mode, do a conversion.
1854 This might be wasteful, but combine.c will
1855 eliminate much of the waste. */
1857 if (GET_MODE (replacements->new)
1858 != GET_MODE (replacements->old))
1861 convert_move (replacements->new,
1862 replacements->old, unsignedp);
1863 seq = gen_sequence ();
1867 seq = gen_move_insn (replacements->new,
1870 emit_insn_before (seq, insert_before);
1873 next = replacements->next;
1874 free (replacements);
1875 replacements = next;
1879 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1880 But don't touch other insns referred to by reg-notes;
1881 we will get them elsewhere. */
1884 if (GET_CODE (note) != INSN_LIST)
1886 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1887 note = XEXP (note, 1);
1891 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1892 See if the rtx expression at *LOC in INSN needs to be changed.
1894 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1895 contain a list of original rtx's and replacements. If we find that we need
1896 to modify this insn by replacing a memory reference with a pseudo or by
1897 making a new MEM to implement a SUBREG, we consult that list to see if
1898 we have already chosen a replacement. If none has already been allocated,
1899 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1900 or the SUBREG, as appropriate, to the pseudo. */
1903 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1905 enum machine_mode promoted_mode;
1908 struct fixup_replacement **replacements;
1913 RTX_CODE code = GET_CODE (x);
1916 struct fixup_replacement *replacement;
1921 if (XEXP (x, 0) == var)
1923 /* Prevent sharing of rtl that might lose. */
1924 rtx sub = copy_rtx (XEXP (var, 0));
1926 if (! validate_change (insn, loc, sub, 0))
1928 rtx y = gen_reg_rtx (GET_MODE (sub));
1931 /* We should be able to replace with a register or all is lost.
1932 Note that we can't use validate_change to verify this, since
1933 we're not caring for replacing all dups simultaneously. */
1934 if (! validate_replace_rtx (*loc, y, insn))
1937 /* Careful! First try to recognize a direct move of the
1938 value, mimicking how things are done in gen_reload wrt
1939 PLUS. Consider what happens when insn is a conditional
1940 move instruction and addsi3 clobbers flags. */
1943 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1944 seq = gen_sequence ();
1947 if (recog_memoized (new_insn) < 0)
1949 /* That failed. Fall back on force_operand and hope. */
1952 sub = force_operand (sub, y);
1954 emit_insn (gen_move_insn (y, sub));
1955 seq = gen_sequence ();
1960 /* Don't separate setter from user. */
1961 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1962 insn = PREV_INSN (insn);
1965 emit_insn_before (seq, insn);
1973 /* If we already have a replacement, use it. Otherwise,
1974 try to fix up this address in case it is invalid. */
1976 replacement = find_fixup_replacement (replacements, var);
1977 if (replacement->new)
1979 *loc = replacement->new;
1983 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1985 /* Unless we are forcing memory to register or we changed the mode,
1986 we can leave things the way they are if the insn is valid. */
1988 INSN_CODE (insn) = -1;
1989 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1990 && recog_memoized (insn) >= 0)
1993 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1997 /* If X contains VAR, we need to unshare it here so that we update
1998 each occurrence separately. But all identical MEMs in one insn
1999 must be replaced with the same rtx because of the possibility of
2002 if (reg_mentioned_p (var, x))
2004 replacement = find_fixup_replacement (replacements, x);
2005 if (replacement->new == 0)
2006 replacement->new = copy_most_rtx (x, no_share);
2008 *loc = x = replacement->new;
2009 code = GET_CODE (x);
2026 /* Note that in some cases those types of expressions are altered
2027 by optimize_bit_field, and do not survive to get here. */
2028 if (XEXP (x, 0) == var
2029 || (GET_CODE (XEXP (x, 0)) == SUBREG
2030 && SUBREG_REG (XEXP (x, 0)) == var))
2032 /* Get TEM as a valid MEM in the mode presently in the insn.
2034 We don't worry about the possibility of MATCH_DUP here; it
2035 is highly unlikely and would be tricky to handle. */
2038 if (GET_CODE (tem) == SUBREG)
2040 if (GET_MODE_BITSIZE (GET_MODE (tem))
2041 > GET_MODE_BITSIZE (GET_MODE (var)))
2043 replacement = find_fixup_replacement (replacements, var);
2044 if (replacement->new == 0)
2045 replacement->new = gen_reg_rtx (GET_MODE (var));
2046 SUBREG_REG (tem) = replacement->new;
2048 /* The following code works only if we have a MEM, so we
2049 need to handle the subreg here. We directly substitute
2050 it assuming that a subreg must be OK here. We already
2051 scheduled a replacement to copy the mem into the
2057 tem = fixup_memory_subreg (tem, insn, 0);
2060 tem = fixup_stack_1 (tem, insn);
2062 /* Unless we want to load from memory, get TEM into the proper mode
2063 for an extract from memory. This can only be done if the
2064 extract is at a constant position and length. */
2066 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2067 && GET_CODE (XEXP (x, 2)) == CONST_INT
2068 && ! mode_dependent_address_p (XEXP (tem, 0))
2069 && ! MEM_VOLATILE_P (tem))
2071 enum machine_mode wanted_mode = VOIDmode;
2072 enum machine_mode is_mode = GET_MODE (tem);
2073 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2075 if (GET_CODE (x) == ZERO_EXTRACT)
2077 enum machine_mode new_mode
2078 = mode_for_extraction (EP_extzv, 1);
2079 if (new_mode != MAX_MACHINE_MODE)
2080 wanted_mode = new_mode;
2082 else if (GET_CODE (x) == SIGN_EXTRACT)
2084 enum machine_mode new_mode
2085 = mode_for_extraction (EP_extv, 1);
2086 if (new_mode != MAX_MACHINE_MODE)
2087 wanted_mode = new_mode;
2090 /* If we have a narrower mode, we can do something. */
2091 if (wanted_mode != VOIDmode
2092 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2094 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2095 rtx old_pos = XEXP (x, 2);
2098 /* If the bytes and bits are counted differently, we
2099 must adjust the offset. */
2100 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2101 offset = (GET_MODE_SIZE (is_mode)
2102 - GET_MODE_SIZE (wanted_mode) - offset);
2104 pos %= GET_MODE_BITSIZE (wanted_mode);
2106 newmem = adjust_address_nv (tem, wanted_mode, offset);
2108 /* Make the change and see if the insn remains valid. */
2109 INSN_CODE (insn) = -1;
2110 XEXP (x, 0) = newmem;
2111 XEXP (x, 2) = GEN_INT (pos);
2113 if (recog_memoized (insn) >= 0)
2116 /* Otherwise, restore old position. XEXP (x, 0) will be
2118 XEXP (x, 2) = old_pos;
2122 /* If we get here, the bitfield extract insn can't accept a memory
2123 reference. Copy the input into a register. */
2125 tem1 = gen_reg_rtx (GET_MODE (tem));
2126 emit_insn_before (gen_move_insn (tem1, tem), insn);
2133 if (SUBREG_REG (x) == var)
2135 /* If this is a special SUBREG made because VAR was promoted
2136 from a wider mode, replace it with VAR and call ourself
2137 recursively, this time saying that the object previously
2138 had its current mode (by virtue of the SUBREG). */
2140 if (SUBREG_PROMOTED_VAR_P (x))
2143 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2148 /* If this SUBREG makes VAR wider, it has become a paradoxical
2149 SUBREG with VAR in memory, but these aren't allowed at this
2150 stage of the compilation. So load VAR into a pseudo and take
2151 a SUBREG of that pseudo. */
2152 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2154 replacement = find_fixup_replacement (replacements, var);
2155 if (replacement->new == 0)
2156 replacement->new = gen_reg_rtx (promoted_mode);
2157 SUBREG_REG (x) = replacement->new;
2161 /* See if we have already found a replacement for this SUBREG.
2162 If so, use it. Otherwise, make a MEM and see if the insn
2163 is recognized. If not, or if we should force MEM into a register,
2164 make a pseudo for this SUBREG. */
2165 replacement = find_fixup_replacement (replacements, x);
2166 if (replacement->new)
2168 *loc = replacement->new;
2172 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2174 INSN_CODE (insn) = -1;
2175 if (! flag_force_mem && recog_memoized (insn) >= 0)
2178 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2184 /* First do special simplification of bit-field references. */
2185 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2186 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2187 optimize_bit_field (x, insn, 0);
2188 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2189 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2190 optimize_bit_field (x, insn, 0);
2192 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2193 into a register and then store it back out. */
2194 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2195 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2196 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2197 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2198 > GET_MODE_SIZE (GET_MODE (var))))
2200 replacement = find_fixup_replacement (replacements, var);
2201 if (replacement->new == 0)
2202 replacement->new = gen_reg_rtx (GET_MODE (var));
2204 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2205 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2208 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2209 insn into a pseudo and store the low part of the pseudo into VAR. */
2210 if (GET_CODE (SET_DEST (x)) == SUBREG
2211 && SUBREG_REG (SET_DEST (x)) == var
2212 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2213 > GET_MODE_SIZE (GET_MODE (var))))
2215 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2216 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2223 rtx dest = SET_DEST (x);
2224 rtx src = SET_SRC (x);
2225 rtx outerdest = dest;
2227 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2228 || GET_CODE (dest) == SIGN_EXTRACT
2229 || GET_CODE (dest) == ZERO_EXTRACT)
2230 dest = XEXP (dest, 0);
2232 if (GET_CODE (src) == SUBREG)
2233 src = SUBREG_REG (src);
2235 /* If VAR does not appear at the top level of the SET
2236 just scan the lower levels of the tree. */
2238 if (src != var && dest != var)
2241 /* We will need to rerecognize this insn. */
2242 INSN_CODE (insn) = -1;
2244 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2245 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2247 /* Since this case will return, ensure we fixup all the
2249 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2250 insn, replacements, no_share);
2251 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2252 insn, replacements, no_share);
2253 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2254 insn, replacements, no_share);
2256 tem = XEXP (outerdest, 0);
2258 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2259 that may appear inside a ZERO_EXTRACT.
2260 This was legitimate when the MEM was a REG. */
2261 if (GET_CODE (tem) == SUBREG
2262 && SUBREG_REG (tem) == var)
2263 tem = fixup_memory_subreg (tem, insn, 0);
2265 tem = fixup_stack_1 (tem, insn);
2267 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2268 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2269 && ! mode_dependent_address_p (XEXP (tem, 0))
2270 && ! MEM_VOLATILE_P (tem))
2272 enum machine_mode wanted_mode;
2273 enum machine_mode is_mode = GET_MODE (tem);
2274 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2276 wanted_mode = mode_for_extraction (EP_insv, 0);
2278 /* If we have a narrower mode, we can do something. */
2279 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2281 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2282 rtx old_pos = XEXP (outerdest, 2);
2285 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2286 offset = (GET_MODE_SIZE (is_mode)
2287 - GET_MODE_SIZE (wanted_mode) - offset);
2289 pos %= GET_MODE_BITSIZE (wanted_mode);
2291 newmem = adjust_address_nv (tem, wanted_mode, offset);
2293 /* Make the change and see if the insn remains valid. */
2294 INSN_CODE (insn) = -1;
2295 XEXP (outerdest, 0) = newmem;
2296 XEXP (outerdest, 2) = GEN_INT (pos);
2298 if (recog_memoized (insn) >= 0)
2301 /* Otherwise, restore old position. XEXP (x, 0) will be
2303 XEXP (outerdest, 2) = old_pos;
2307 /* If we get here, the bit-field store doesn't allow memory
2308 or isn't located at a constant position. Load the value into
2309 a register, do the store, and put it back into memory. */
2311 tem1 = gen_reg_rtx (GET_MODE (tem));
2312 emit_insn_before (gen_move_insn (tem1, tem), insn);
2313 emit_insn_after (gen_move_insn (tem, tem1), insn);
2314 XEXP (outerdest, 0) = tem1;
2318 /* STRICT_LOW_PART is a no-op on memory references
2319 and it can cause combinations to be unrecognizable,
2322 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2323 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2325 /* A valid insn to copy VAR into or out of a register
2326 must be left alone, to avoid an infinite loop here.
2327 If the reference to VAR is by a subreg, fix that up,
2328 since SUBREG is not valid for a memref.
2329 Also fix up the address of the stack slot.
2331 Note that we must not try to recognize the insn until
2332 after we know that we have valid addresses and no
2333 (subreg (mem ...) ...) constructs, since these interfere
2334 with determining the validity of the insn. */
2336 if ((SET_SRC (x) == var
2337 || (GET_CODE (SET_SRC (x)) == SUBREG
2338 && SUBREG_REG (SET_SRC (x)) == var))
2339 && (GET_CODE (SET_DEST (x)) == REG
2340 || (GET_CODE (SET_DEST (x)) == SUBREG
2341 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2342 && GET_MODE (var) == promoted_mode
2343 && x == single_set (insn))
2347 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2348 if (replacement->new)
2349 SET_SRC (x) = replacement->new;
2350 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2351 SET_SRC (x) = replacement->new
2352 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2354 SET_SRC (x) = replacement->new
2355 = fixup_stack_1 (SET_SRC (x), insn);
2357 if (recog_memoized (insn) >= 0)
2360 /* INSN is not valid, but we know that we want to
2361 copy SET_SRC (x) to SET_DEST (x) in some way. So
2362 we generate the move and see whether it requires more
2363 than one insn. If it does, we emit those insns and
2364 delete INSN. Otherwise, we an just replace the pattern
2365 of INSN; we have already verified above that INSN has
2366 no other function that to do X. */
2368 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2369 if (GET_CODE (pat) == SEQUENCE)
2371 last = emit_insn_before (pat, insn);
2373 /* INSN might have REG_RETVAL or other important notes, so
2374 we need to store the pattern of the last insn in the
2375 sequence into INSN similarly to the normal case. LAST
2376 should not have REG_NOTES, but we allow them if INSN has
2378 if (REG_NOTES (last) && REG_NOTES (insn))
2380 if (REG_NOTES (last))
2381 REG_NOTES (insn) = REG_NOTES (last);
2382 PATTERN (insn) = PATTERN (last);
2387 PATTERN (insn) = pat;
2392 if ((SET_DEST (x) == var
2393 || (GET_CODE (SET_DEST (x)) == SUBREG
2394 && SUBREG_REG (SET_DEST (x)) == var))
2395 && (GET_CODE (SET_SRC (x)) == REG
2396 || (GET_CODE (SET_SRC (x)) == SUBREG
2397 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2398 && GET_MODE (var) == promoted_mode
2399 && x == single_set (insn))
2403 if (GET_CODE (SET_DEST (x)) == SUBREG)
2404 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2406 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2408 if (recog_memoized (insn) >= 0)
2411 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2412 if (GET_CODE (pat) == SEQUENCE)
2414 last = emit_insn_before (pat, insn);
2416 /* INSN might have REG_RETVAL or other important notes, so
2417 we need to store the pattern of the last insn in the
2418 sequence into INSN similarly to the normal case. LAST
2419 should not have REG_NOTES, but we allow them if INSN has
2421 if (REG_NOTES (last) && REG_NOTES (insn))
2423 if (REG_NOTES (last))
2424 REG_NOTES (insn) = REG_NOTES (last);
2425 PATTERN (insn) = PATTERN (last);
2430 PATTERN (insn) = pat;
2435 /* Otherwise, storing into VAR must be handled specially
2436 by storing into a temporary and copying that into VAR
2437 with a new insn after this one. Note that this case
2438 will be used when storing into a promoted scalar since
2439 the insn will now have different modes on the input
2440 and output and hence will be invalid (except for the case
2441 of setting it to a constant, which does not need any
2442 change if it is valid). We generate extra code in that case,
2443 but combine.c will eliminate it. */
2448 rtx fixeddest = SET_DEST (x);
2450 /* STRICT_LOW_PART can be discarded, around a MEM. */
2451 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2452 fixeddest = XEXP (fixeddest, 0);
2453 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2454 if (GET_CODE (fixeddest) == SUBREG)
2456 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2457 promoted_mode = GET_MODE (fixeddest);
2460 fixeddest = fixup_stack_1 (fixeddest, insn);
2462 temp = gen_reg_rtx (promoted_mode);
2464 emit_insn_after (gen_move_insn (fixeddest,
2465 gen_lowpart (GET_MODE (fixeddest),
2469 SET_DEST (x) = temp;
2477 /* Nothing special about this RTX; fix its operands. */
2479 fmt = GET_RTX_FORMAT (code);
2480 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2483 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2485 else if (fmt[i] == 'E')
2488 for (j = 0; j < XVECLEN (x, i); j++)
2489 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2490 insn, replacements, no_share);
2495 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2496 return an rtx (MEM:m1 newaddr) which is equivalent.
2497 If any insns must be emitted to compute NEWADDR, put them before INSN.
2499 UNCRITICAL nonzero means accept paradoxical subregs.
2500 This is used for subregs found inside REG_NOTES. */
2503 fixup_memory_subreg (x, insn, uncritical)
2508 int offset = SUBREG_BYTE (x);
2509 rtx addr = XEXP (SUBREG_REG (x), 0);
2510 enum machine_mode mode = GET_MODE (x);
2513 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2514 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2518 if (!flag_force_addr
2519 && memory_address_p (mode, plus_constant (addr, offset)))
2520 /* Shortcut if no insns need be emitted. */
2521 return adjust_address (SUBREG_REG (x), mode, offset);
2524 result = adjust_address (SUBREG_REG (x), mode, offset);
2525 emit_insn_before (gen_sequence (), insn);
2530 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2531 Replace subexpressions of X in place.
2532 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2533 Otherwise return X, with its contents possibly altered.
2535 If any insns must be emitted to compute NEWADDR, put them before INSN.
2537 UNCRITICAL is as in fixup_memory_subreg. */
2540 walk_fixup_memory_subreg (x, insn, uncritical)
2552 code = GET_CODE (x);
2554 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2555 return fixup_memory_subreg (x, insn, uncritical);
2557 /* Nothing special about this RTX; fix its operands. */
2559 fmt = GET_RTX_FORMAT (code);
2560 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2563 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2564 else if (fmt[i] == 'E')
2567 for (j = 0; j < XVECLEN (x, i); j++)
2569 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2575 /* For each memory ref within X, if it refers to a stack slot
2576 with an out of range displacement, put the address in a temp register
2577 (emitting new insns before INSN to load these registers)
2578 and alter the memory ref to use that register.
2579 Replace each such MEM rtx with a copy, to avoid clobberage. */
2582 fixup_stack_1 (x, insn)
2587 RTX_CODE code = GET_CODE (x);
2592 rtx ad = XEXP (x, 0);
2593 /* If we have address of a stack slot but it's not valid
2594 (displacement is too large), compute the sum in a register. */
2595 if (GET_CODE (ad) == PLUS
2596 && GET_CODE (XEXP (ad, 0)) == REG
2597 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2598 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2599 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2600 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2601 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2603 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2604 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2605 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2606 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2609 if (memory_address_p (GET_MODE (x), ad))
2613 temp = copy_to_reg (ad);
2614 seq = gen_sequence ();
2616 emit_insn_before (seq, insn);
2617 return replace_equiv_address (x, temp);
2622 fmt = GET_RTX_FORMAT (code);
2623 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2626 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2627 else if (fmt[i] == 'E')
2630 for (j = 0; j < XVECLEN (x, i); j++)
2631 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2637 /* Optimization: a bit-field instruction whose field
2638 happens to be a byte or halfword in memory
2639 can be changed to a move instruction.
2641 We call here when INSN is an insn to examine or store into a bit-field.
2642 BODY is the SET-rtx to be altered.
2644 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2645 (Currently this is called only from function.c, and EQUIV_MEM
2649 optimize_bit_field (body, insn, equiv_mem)
2657 enum machine_mode mode;
2659 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2660 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2661 bitfield = SET_DEST (body), destflag = 1;
2663 bitfield = SET_SRC (body), destflag = 0;
2665 /* First check that the field being stored has constant size and position
2666 and is in fact a byte or halfword suitably aligned. */
2668 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2669 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2670 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2672 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2676 /* Now check that the containing word is memory, not a register,
2677 and that it is safe to change the machine mode. */
2679 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2680 memref = XEXP (bitfield, 0);
2681 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2683 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2684 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2685 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2686 memref = SUBREG_REG (XEXP (bitfield, 0));
2687 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2689 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2690 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2693 && ! mode_dependent_address_p (XEXP (memref, 0))
2694 && ! MEM_VOLATILE_P (memref))
2696 /* Now adjust the address, first for any subreg'ing
2697 that we are now getting rid of,
2698 and then for which byte of the word is wanted. */
2700 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2703 /* Adjust OFFSET to count bits from low-address byte. */
2704 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2705 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2706 - offset - INTVAL (XEXP (bitfield, 1)));
2708 /* Adjust OFFSET to count bytes from low-address byte. */
2709 offset /= BITS_PER_UNIT;
2710 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2712 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2713 / UNITS_PER_WORD) * UNITS_PER_WORD;
2714 if (BYTES_BIG_ENDIAN)
2715 offset -= (MIN (UNITS_PER_WORD,
2716 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2717 - MIN (UNITS_PER_WORD,
2718 GET_MODE_SIZE (GET_MODE (memref))));
2722 memref = adjust_address (memref, mode, offset);
2723 insns = get_insns ();
2725 emit_insns_before (insns, insn);
2727 /* Store this memory reference where
2728 we found the bit field reference. */
2732 validate_change (insn, &SET_DEST (body), memref, 1);
2733 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2735 rtx src = SET_SRC (body);
2736 while (GET_CODE (src) == SUBREG
2737 && SUBREG_BYTE (src) == 0)
2738 src = SUBREG_REG (src);
2739 if (GET_MODE (src) != GET_MODE (memref))
2740 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2741 validate_change (insn, &SET_SRC (body), src, 1);
2743 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2744 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2745 /* This shouldn't happen because anything that didn't have
2746 one of these modes should have got converted explicitly
2747 and then referenced through a subreg.
2748 This is so because the original bit-field was
2749 handled by agg_mode and so its tree structure had
2750 the same mode that memref now has. */
2755 rtx dest = SET_DEST (body);
2757 while (GET_CODE (dest) == SUBREG
2758 && SUBREG_BYTE (dest) == 0
2759 && (GET_MODE_CLASS (GET_MODE (dest))
2760 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2761 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2763 dest = SUBREG_REG (dest);
2765 validate_change (insn, &SET_DEST (body), dest, 1);
2767 if (GET_MODE (dest) == GET_MODE (memref))
2768 validate_change (insn, &SET_SRC (body), memref, 1);
2771 /* Convert the mem ref to the destination mode. */
2772 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2775 convert_move (newreg, memref,
2776 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2780 validate_change (insn, &SET_SRC (body), newreg, 1);
2784 /* See if we can convert this extraction or insertion into
2785 a simple move insn. We might not be able to do so if this
2786 was, for example, part of a PARALLEL.
2788 If we succeed, write out any needed conversions. If we fail,
2789 it is hard to guess why we failed, so don't do anything
2790 special; just let the optimization be suppressed. */
2792 if (apply_change_group () && seq)
2793 emit_insns_before (seq, insn);
2798 /* These routines are responsible for converting virtual register references
2799 to the actual hard register references once RTL generation is complete.
2801 The following four variables are used for communication between the
2802 routines. They contain the offsets of the virtual registers from their
2803 respective hard registers. */
2805 static int in_arg_offset;
2806 static int var_offset;
2807 static int dynamic_offset;
2808 static int out_arg_offset;
2809 static int cfa_offset;
2811 /* In most machines, the stack pointer register is equivalent to the bottom
2814 #ifndef STACK_POINTER_OFFSET
2815 #define STACK_POINTER_OFFSET 0
2818 /* If not defined, pick an appropriate default for the offset of dynamically
2819 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2820 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2822 #ifndef STACK_DYNAMIC_OFFSET
2824 /* The bottom of the stack points to the actual arguments. If
2825 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2826 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2827 stack space for register parameters is not pushed by the caller, but
2828 rather part of the fixed stack areas and hence not included in
2829 `current_function_outgoing_args_size'. Nevertheless, we must allow
2830 for it when allocating stack dynamic objects. */
2832 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2833 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2834 ((ACCUMULATE_OUTGOING_ARGS \
2835 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2836 + (STACK_POINTER_OFFSET)) \
2839 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2840 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2841 + (STACK_POINTER_OFFSET))
2845 /* On most machines, the CFA coincides with the first incoming parm. */
2847 #ifndef ARG_POINTER_CFA_OFFSET
2848 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2851 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2852 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2853 register, for later use if we do need to force REG into the stack. REG is
2854 overwritten by the MEM like in put_reg_into_stack. */
2857 gen_mem_addressof (reg, decl)
2861 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2864 /* Calculate this before we start messing with decl's RTL. */
2865 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2867 /* If the original REG was a user-variable, then so is the REG whose
2868 address is being taken. Likewise for unchanging. */
2869 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2870 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2872 PUT_CODE (reg, MEM);
2873 MEM_ATTRS (reg) = 0;
2878 tree type = TREE_TYPE (decl);
2879 enum machine_mode decl_mode
2880 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2881 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2882 : DECL_RTL_IF_SET (decl));
2884 PUT_MODE (reg, decl_mode);
2886 /* Clear DECL_RTL momentarily so functions below will work
2887 properly, then set it again. */
2888 if (DECL_P (decl) && decl_rtl == reg)
2889 SET_DECL_RTL (decl, 0);
2891 set_mem_attributes (reg, decl, 1);
2892 set_mem_alias_set (reg, set);
2894 if (DECL_P (decl) && decl_rtl == reg)
2895 SET_DECL_RTL (decl, reg);
2897 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2898 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2901 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2906 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2909 flush_addressof (decl)
2912 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2913 && DECL_RTL (decl) != 0
2914 && GET_CODE (DECL_RTL (decl)) == MEM
2915 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2916 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2917 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2920 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2923 put_addressof_into_stack (r, ht)
2925 struct hash_table *ht;
2928 int volatile_p, used_p;
2930 rtx reg = XEXP (r, 0);
2932 if (GET_CODE (reg) != REG)
2935 decl = ADDRESSOF_DECL (r);
2938 type = TREE_TYPE (decl);
2939 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2940 && TREE_THIS_VOLATILE (decl));
2941 used_p = (TREE_USED (decl)
2942 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2951 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2952 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2955 /* List of replacements made below in purge_addressof_1 when creating
2956 bitfield insertions. */
2957 static rtx purge_bitfield_addressof_replacements;
2959 /* List of replacements made below in purge_addressof_1 for patterns
2960 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2961 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2962 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2963 enough in complex cases, e.g. when some field values can be
2964 extracted by usage MEM with narrower mode. */
2965 static rtx purge_addressof_replacements;
2967 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2968 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2969 the stack. If the function returns FALSE then the replacement could not
2973 purge_addressof_1 (loc, insn, force, store, ht)
2977 struct hash_table *ht;
2985 /* Re-start here to avoid recursion in common cases. */
2992 code = GET_CODE (x);
2994 /* If we don't return in any of the cases below, we will recurse inside
2995 the RTX, which will normally result in any ADDRESSOF being forced into
2999 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3000 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3003 else if (code == ADDRESSOF)
3007 if (GET_CODE (XEXP (x, 0)) != MEM)
3009 put_addressof_into_stack (x, ht);
3013 /* We must create a copy of the rtx because it was created by
3014 overwriting a REG rtx which is always shared. */
3015 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3016 if (validate_change (insn, loc, sub, 0)
3017 || validate_replace_rtx (x, sub, insn))
3021 sub = force_operand (sub, NULL_RTX);
3022 if (! validate_change (insn, loc, sub, 0)
3023 && ! validate_replace_rtx (x, sub, insn))
3026 insns = gen_sequence ();
3028 emit_insn_before (insns, insn);
3032 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3034 rtx sub = XEXP (XEXP (x, 0), 0);
3036 if (GET_CODE (sub) == MEM)
3037 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3038 else if (GET_CODE (sub) == REG
3039 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3041 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3043 int size_x, size_sub;
3047 /* When processing REG_NOTES look at the list of
3048 replacements done on the insn to find the register that X
3052 for (tem = purge_bitfield_addressof_replacements;
3054 tem = XEXP (XEXP (tem, 1), 1))
3055 if (rtx_equal_p (x, XEXP (tem, 0)))
3057 *loc = XEXP (XEXP (tem, 1), 0);
3061 /* See comment for purge_addressof_replacements. */
3062 for (tem = purge_addressof_replacements;
3064 tem = XEXP (XEXP (tem, 1), 1))
3065 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3067 rtx z = XEXP (XEXP (tem, 1), 0);
3069 if (GET_MODE (x) == GET_MODE (z)
3070 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3071 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3074 /* It can happen that the note may speak of things
3075 in a wider (or just different) mode than the
3076 code did. This is especially true of
3079 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3082 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3083 && (GET_MODE_SIZE (GET_MODE (x))
3084 > GET_MODE_SIZE (GET_MODE (z))))
3086 /* This can occur as a result in invalid
3087 pointer casts, e.g. float f; ...
3088 *(long long int *)&f.
3089 ??? We could emit a warning here, but
3090 without a line number that wouldn't be
3092 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3095 z = gen_lowpart (GET_MODE (x), z);
3101 /* Sometimes we may not be able to find the replacement. For
3102 example when the original insn was a MEM in a wider mode,
3103 and the note is part of a sign extension of a narrowed
3104 version of that MEM. Gcc testcase compile/990829-1.c can
3105 generate an example of this situation. Rather than complain
3106 we return false, which will prompt our caller to remove the
3111 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3112 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3114 /* Don't even consider working with paradoxical subregs,
3115 or the moral equivalent seen here. */
3116 if (size_x <= size_sub
3117 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3119 /* Do a bitfield insertion to mirror what would happen
3126 rtx p = PREV_INSN (insn);
3129 val = gen_reg_rtx (GET_MODE (x));
3130 if (! validate_change (insn, loc, val, 0))
3132 /* Discard the current sequence and put the
3133 ADDRESSOF on stack. */
3137 seq = gen_sequence ();
3139 emit_insn_before (seq, insn);
3140 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3144 store_bit_field (sub, size_x, 0, GET_MODE (x),
3145 val, GET_MODE_SIZE (GET_MODE (sub)));
3147 /* Make sure to unshare any shared rtl that store_bit_field
3148 might have created. */
3149 unshare_all_rtl_again (get_insns ());
3151 seq = gen_sequence ();
3153 p = emit_insn_after (seq, insn);
3154 if (NEXT_INSN (insn))
3155 compute_insns_for_mem (NEXT_INSN (insn),
3156 p ? NEXT_INSN (p) : NULL_RTX,
3161 rtx p = PREV_INSN (insn);
3164 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3165 GET_MODE (x), GET_MODE (x),
3166 GET_MODE_SIZE (GET_MODE (sub)));
3168 if (! validate_change (insn, loc, val, 0))
3170 /* Discard the current sequence and put the
3171 ADDRESSOF on stack. */
3176 seq = gen_sequence ();
3178 emit_insn_before (seq, insn);
3179 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3183 /* Remember the replacement so that the same one can be done
3184 on the REG_NOTES. */
3185 purge_bitfield_addressof_replacements
3186 = gen_rtx_EXPR_LIST (VOIDmode, x,
3189 purge_bitfield_addressof_replacements));
3191 /* We replaced with a reg -- all done. */
3196 else if (validate_change (insn, loc, sub, 0))
3198 /* Remember the replacement so that the same one can be done
3199 on the REG_NOTES. */
3200 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3204 for (tem = purge_addressof_replacements;
3206 tem = XEXP (XEXP (tem, 1), 1))
3207 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3209 XEXP (XEXP (tem, 1), 0) = sub;
3212 purge_addressof_replacements
3213 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3214 gen_rtx_EXPR_LIST (VOIDmode, sub,
3215 purge_addressof_replacements));
3223 /* Scan all subexpressions. */
3224 fmt = GET_RTX_FORMAT (code);
3225 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3228 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3229 else if (*fmt == 'E')
3230 for (j = 0; j < XVECLEN (x, i); j++)
3231 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3237 /* Return a new hash table entry in HT. */
3239 static struct hash_entry *
3240 insns_for_mem_newfunc (he, ht, k)
3241 struct hash_entry *he;
3242 struct hash_table *ht;
3243 hash_table_key k ATTRIBUTE_UNUSED;
3245 struct insns_for_mem_entry *ifmhe;
3249 ifmhe = ((struct insns_for_mem_entry *)
3250 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3251 ifmhe->insns = NULL_RTX;
3256 /* Return a hash value for K, a REG. */
3258 static unsigned long
3259 insns_for_mem_hash (k)
3262 /* K is really a RTX. Just use the address as the hash value. */
3263 return (unsigned long) k;
3266 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3269 insns_for_mem_comp (k1, k2)
3276 struct insns_for_mem_walk_info
3278 /* The hash table that we are using to record which INSNs use which
3280 struct hash_table *ht;
3282 /* The INSN we are currently processing. */
3285 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3286 to find the insns that use the REGs in the ADDRESSOFs. */
3290 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3291 that might be used in an ADDRESSOF expression, record this INSN in
3292 the hash table given by DATA (which is really a pointer to an
3293 insns_for_mem_walk_info structure). */
3296 insns_for_mem_walk (r, data)
3300 struct insns_for_mem_walk_info *ifmwi
3301 = (struct insns_for_mem_walk_info *) data;
3303 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3304 && GET_CODE (XEXP (*r, 0)) == REG)
3305 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3306 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3308 /* Lookup this MEM in the hashtable, creating it if necessary. */
3309 struct insns_for_mem_entry *ifme
3310 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3315 /* If we have not already recorded this INSN, do so now. Since
3316 we process the INSNs in order, we know that if we have
3317 recorded it it must be at the front of the list. */
3318 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3319 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3326 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3327 which REGs in HT. */
3330 compute_insns_for_mem (insns, last_insn, ht)
3333 struct hash_table *ht;
3336 struct insns_for_mem_walk_info ifmwi;
3339 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3340 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3344 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3348 /* Helper function for purge_addressof called through for_each_rtx.
3349 Returns true iff the rtl is an ADDRESSOF. */
3352 is_addressof (rtl, data)
3354 void *data ATTRIBUTE_UNUSED;
3356 return GET_CODE (*rtl) == ADDRESSOF;
3359 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3360 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3364 purge_addressof (insns)
3368 struct hash_table ht;
3370 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3371 requires a fixup pass over the instruction stream to correct
3372 INSNs that depended on the REG being a REG, and not a MEM. But,
3373 these fixup passes are slow. Furthermore, most MEMs are not
3374 mentioned in very many instructions. So, we speed up the process
3375 by pre-calculating which REGs occur in which INSNs; that allows
3376 us to perform the fixup passes much more quickly. */
3377 hash_table_init (&ht,
3378 insns_for_mem_newfunc,
3380 insns_for_mem_comp);
3381 compute_insns_for_mem (insns, NULL_RTX, &ht);
3383 for (insn = insns; insn; insn = NEXT_INSN (insn))
3384 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3385 || GET_CODE (insn) == CALL_INSN)
3387 if (! purge_addressof_1 (&PATTERN (insn), insn,
3388 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3389 /* If we could not replace the ADDRESSOFs in the insn,
3390 something is wrong. */
3393 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3395 /* If we could not replace the ADDRESSOFs in the insn's notes,
3396 we can just remove the offending notes instead. */
3399 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3401 /* If we find a REG_RETVAL note then the insn is a libcall.
3402 Such insns must have REG_EQUAL notes as well, in order
3403 for later passes of the compiler to work. So it is not
3404 safe to delete the notes here, and instead we abort. */
3405 if (REG_NOTE_KIND (note) == REG_RETVAL)
3407 if (for_each_rtx (¬e, is_addressof, NULL))
3408 remove_note (insn, note);
3414 hash_table_free (&ht);
3415 purge_bitfield_addressof_replacements = 0;
3416 purge_addressof_replacements = 0;
3418 /* REGs are shared. purge_addressof will destructively replace a REG
3419 with a MEM, which creates shared MEMs.
3421 Unfortunately, the children of put_reg_into_stack assume that MEMs
3422 referring to the same stack slot are shared (fixup_var_refs and
3423 the associated hash table code).
3425 So, we have to do another unsharing pass after we have flushed any
3426 REGs that had their address taken into the stack.
3428 It may be worth tracking whether or not we converted any REGs into
3429 MEMs to avoid this overhead when it is not needed. */
3430 unshare_all_rtl_again (get_insns ());
3433 /* Convert a SET of a hard subreg to a set of the appropriate hard
3434 register. A subroutine of purge_hard_subreg_sets. */
3437 purge_single_hard_subreg_set (pattern)
3440 rtx reg = SET_DEST (pattern);
3441 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3444 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3445 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3447 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3448 GET_MODE (SUBREG_REG (reg)),
3451 reg = SUBREG_REG (reg);
3455 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3457 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3458 SET_DEST (pattern) = reg;
3462 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3463 only such SETs that we expect to see are those left in because
3464 integrate can't handle sets of parts of a return value register.
3466 We don't use alter_subreg because we only want to eliminate subregs
3467 of hard registers. */
3470 purge_hard_subreg_sets (insn)
3473 for (; insn; insn = NEXT_INSN (insn))
3477 rtx pattern = PATTERN (insn);
3478 switch (GET_CODE (pattern))
3481 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3482 purge_single_hard_subreg_set (pattern);
3487 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3489 rtx inner_pattern = XVECEXP (pattern, 0, j);
3490 if (GET_CODE (inner_pattern) == SET
3491 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3492 purge_single_hard_subreg_set (inner_pattern);
3503 /* Pass through the INSNS of function FNDECL and convert virtual register
3504 references to hard register references. */
3507 instantiate_virtual_regs (fndecl, insns)
3514 /* Compute the offsets to use for this function. */
3515 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3516 var_offset = STARTING_FRAME_OFFSET;
3517 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3518 out_arg_offset = STACK_POINTER_OFFSET;
3519 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3521 /* Scan all variables and parameters of this function. For each that is
3522 in memory, instantiate all virtual registers if the result is a valid
3523 address. If not, we do it later. That will handle most uses of virtual
3524 regs on many machines. */
3525 instantiate_decls (fndecl, 1);
3527 /* Initialize recognition, indicating that volatile is OK. */
3530 /* Scan through all the insns, instantiating every virtual register still
3532 for (insn = insns; insn; insn = NEXT_INSN (insn))
3533 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3534 || GET_CODE (insn) == CALL_INSN)
3536 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3537 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3538 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3539 if (GET_CODE (insn) == CALL_INSN)
3540 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3544 /* Instantiate the stack slots for the parm registers, for later use in
3545 addressof elimination. */
3546 for (i = 0; i < max_parm_reg; ++i)
3547 if (parm_reg_stack_loc[i])
3548 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3550 /* Now instantiate the remaining register equivalences for debugging info.
3551 These will not be valid addresses. */
3552 instantiate_decls (fndecl, 0);
3554 /* Indicate that, from now on, assign_stack_local should use
3555 frame_pointer_rtx. */
3556 virtuals_instantiated = 1;
3559 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3560 all virtual registers in their DECL_RTL's.
3562 If VALID_ONLY, do this only if the resulting address is still valid.
3563 Otherwise, always do it. */
3566 instantiate_decls (fndecl, valid_only)
3572 /* Process all parameters of the function. */
3573 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3575 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3576 HOST_WIDE_INT size_rtl;
3578 instantiate_decl (DECL_RTL (decl), size, valid_only);
3580 /* If the parameter was promoted, then the incoming RTL mode may be
3581 larger than the declared type size. We must use the larger of
3583 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3584 size = MAX (size_rtl, size);
3585 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3588 /* Now process all variables defined in the function or its subblocks. */
3589 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3592 /* Subroutine of instantiate_decls: Process all decls in the given
3593 BLOCK node and all its subblocks. */
3596 instantiate_decls_1 (let, valid_only)
3602 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3603 if (DECL_RTL_SET_P (t))
3604 instantiate_decl (DECL_RTL (t),
3605 int_size_in_bytes (TREE_TYPE (t)),
3608 /* Process all subblocks. */
3609 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3610 instantiate_decls_1 (t, valid_only);
3613 /* Subroutine of the preceding procedures: Given RTL representing a
3614 decl and the size of the object, do any instantiation required.
3616 If VALID_ONLY is non-zero, it means that the RTL should only be
3617 changed if the new address is valid. */
3620 instantiate_decl (x, size, valid_only)
3625 enum machine_mode mode;
3628 /* If this is not a MEM, no need to do anything. Similarly if the
3629 address is a constant or a register that is not a virtual register. */
3631 if (x == 0 || GET_CODE (x) != MEM)
3635 if (CONSTANT_P (addr)
3636 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3637 || (GET_CODE (addr) == REG
3638 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3639 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3642 /* If we should only do this if the address is valid, copy the address.
3643 We need to do this so we can undo any changes that might make the
3644 address invalid. This copy is unfortunate, but probably can't be
3648 addr = copy_rtx (addr);
3650 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3652 if (valid_only && size >= 0)
3654 unsigned HOST_WIDE_INT decl_size = size;
3656 /* Now verify that the resulting address is valid for every integer or
3657 floating-point mode up to and including SIZE bytes long. We do this
3658 since the object might be accessed in any mode and frame addresses
3661 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3662 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3663 mode = GET_MODE_WIDER_MODE (mode))
3664 if (! memory_address_p (mode, addr))
3667 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3668 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3669 mode = GET_MODE_WIDER_MODE (mode))
3670 if (! memory_address_p (mode, addr))
3674 /* Put back the address now that we have updated it and we either know
3675 it is valid or we don't care whether it is valid. */
3680 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3681 is a virtual register, return the equivalent hard register and set the
3682 offset indirectly through the pointer. Otherwise, return 0. */
3685 instantiate_new_reg (x, poffset)
3687 HOST_WIDE_INT *poffset;
3690 HOST_WIDE_INT offset;
3692 if (x == virtual_incoming_args_rtx)
3693 new = arg_pointer_rtx, offset = in_arg_offset;
3694 else if (x == virtual_stack_vars_rtx)
3695 new = frame_pointer_rtx, offset = var_offset;
3696 else if (x == virtual_stack_dynamic_rtx)
3697 new = stack_pointer_rtx, offset = dynamic_offset;
3698 else if (x == virtual_outgoing_args_rtx)
3699 new = stack_pointer_rtx, offset = out_arg_offset;
3700 else if (x == virtual_cfa_rtx)
3701 new = arg_pointer_rtx, offset = cfa_offset;
3709 /* Given a pointer to a piece of rtx and an optional pointer to the
3710 containing object, instantiate any virtual registers present in it.
3712 If EXTRA_INSNS, we always do the replacement and generate
3713 any extra insns before OBJECT. If it zero, we do nothing if replacement
3716 Return 1 if we either had nothing to do or if we were able to do the
3717 needed replacement. Return 0 otherwise; we only return zero if
3718 EXTRA_INSNS is zero.
3720 We first try some simple transformations to avoid the creation of extra
3724 instantiate_virtual_regs_1 (loc, object, extra_insns)
3732 HOST_WIDE_INT offset = 0;
3738 /* Re-start here to avoid recursion in common cases. */
3745 code = GET_CODE (x);
3747 /* Check for some special cases. */
3765 /* We are allowed to set the virtual registers. This means that
3766 the actual register should receive the source minus the
3767 appropriate offset. This is used, for example, in the handling
3768 of non-local gotos. */
3769 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3771 rtx src = SET_SRC (x);
3773 /* We are setting the register, not using it, so the relevant
3774 offset is the negative of the offset to use were we using
3777 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3779 /* The only valid sources here are PLUS or REG. Just do
3780 the simplest possible thing to handle them. */
3781 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3785 if (GET_CODE (src) != REG)
3786 temp = force_operand (src, NULL_RTX);
3789 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3793 emit_insns_before (seq, object);
3796 if (! validate_change (object, &SET_SRC (x), temp, 0)
3803 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3808 /* Handle special case of virtual register plus constant. */
3809 if (CONSTANT_P (XEXP (x, 1)))
3811 rtx old, new_offset;
3813 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3814 if (GET_CODE (XEXP (x, 0)) == PLUS)
3816 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3818 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3820 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3829 #ifdef POINTERS_EXTEND_UNSIGNED
3830 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3831 we can commute the PLUS and SUBREG because pointers into the
3832 frame are well-behaved. */
3833 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3834 && GET_CODE (XEXP (x, 1)) == CONST_INT
3836 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3838 && validate_change (object, loc,
3839 plus_constant (gen_lowpart (ptr_mode,
3842 + INTVAL (XEXP (x, 1))),
3846 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3848 /* We know the second operand is a constant. Unless the
3849 first operand is a REG (which has been already checked),
3850 it needs to be checked. */
3851 if (GET_CODE (XEXP (x, 0)) != REG)
3859 new_offset = plus_constant (XEXP (x, 1), offset);
3861 /* If the new constant is zero, try to replace the sum with just
3863 if (new_offset == const0_rtx
3864 && validate_change (object, loc, new, 0))
3867 /* Next try to replace the register and new offset.
3868 There are two changes to validate here and we can't assume that
3869 in the case of old offset equals new just changing the register
3870 will yield a valid insn. In the interests of a little efficiency,
3871 however, we only call validate change once (we don't queue up the
3872 changes and then call apply_change_group). */
3876 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3877 : (XEXP (x, 0) = new,
3878 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3886 /* Otherwise copy the new constant into a register and replace
3887 constant with that register. */
3888 temp = gen_reg_rtx (Pmode);
3890 if (validate_change (object, &XEXP (x, 1), temp, 0))
3891 emit_insn_before (gen_move_insn (temp, new_offset), object);
3894 /* If that didn't work, replace this expression with a
3895 register containing the sum. */
3898 new = gen_rtx_PLUS (Pmode, new, new_offset);
3901 temp = force_operand (new, NULL_RTX);
3905 emit_insns_before (seq, object);
3906 if (! validate_change (object, loc, temp, 0)
3907 && ! validate_replace_rtx (x, temp, object))
3915 /* Fall through to generic two-operand expression case. */
3921 case DIV: case UDIV:
3922 case MOD: case UMOD:
3923 case AND: case IOR: case XOR:
3924 case ROTATERT: case ROTATE:
3925 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3927 case GE: case GT: case GEU: case GTU:
3928 case LE: case LT: case LEU: case LTU:
3929 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3930 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3935 /* Most cases of MEM that convert to valid addresses have already been
3936 handled by our scan of decls. The only special handling we
3937 need here is to make a copy of the rtx to ensure it isn't being
3938 shared if we have to change it to a pseudo.
3940 If the rtx is a simple reference to an address via a virtual register,
3941 it can potentially be shared. In such cases, first try to make it
3942 a valid address, which can also be shared. Otherwise, copy it and
3945 First check for common cases that need no processing. These are
3946 usually due to instantiation already being done on a previous instance
3950 if (CONSTANT_ADDRESS_P (temp)
3951 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3952 || temp == arg_pointer_rtx
3954 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3955 || temp == hard_frame_pointer_rtx
3957 || temp == frame_pointer_rtx)
3960 if (GET_CODE (temp) == PLUS
3961 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3962 && (XEXP (temp, 0) == frame_pointer_rtx
3963 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3964 || XEXP (temp, 0) == hard_frame_pointer_rtx
3966 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3967 || XEXP (temp, 0) == arg_pointer_rtx
3972 if (temp == virtual_stack_vars_rtx
3973 || temp == virtual_incoming_args_rtx
3974 || (GET_CODE (temp) == PLUS
3975 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3976 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3977 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3979 /* This MEM may be shared. If the substitution can be done without
3980 the need to generate new pseudos, we want to do it in place
3981 so all copies of the shared rtx benefit. The call below will
3982 only make substitutions if the resulting address is still
3985 Note that we cannot pass X as the object in the recursive call
3986 since the insn being processed may not allow all valid
3987 addresses. However, if we were not passed on object, we can
3988 only modify X without copying it if X will have a valid
3991 ??? Also note that this can still lose if OBJECT is an insn that
3992 has less restrictions on an address that some other insn.
3993 In that case, we will modify the shared address. This case
3994 doesn't seem very likely, though. One case where this could
3995 happen is in the case of a USE or CLOBBER reference, but we
3996 take care of that below. */
3998 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3999 object ? object : x, 0))
4002 /* Otherwise make a copy and process that copy. We copy the entire
4003 RTL expression since it might be a PLUS which could also be
4005 *loc = x = copy_rtx (x);
4008 /* Fall through to generic unary operation case. */
4011 case STRICT_LOW_PART:
4013 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4014 case SIGN_EXTEND: case ZERO_EXTEND:
4015 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4016 case FLOAT: case FIX:
4017 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4021 /* These case either have just one operand or we know that we need not
4022 check the rest of the operands. */
4028 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4029 go ahead and make the invalid one, but do it to a copy. For a REG,
4030 just make the recursive call, since there's no chance of a problem. */
4032 if ((GET_CODE (XEXP (x, 0)) == MEM
4033 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4035 || (GET_CODE (XEXP (x, 0)) == REG
4036 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4039 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4044 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4045 in front of this insn and substitute the temporary. */
4046 if ((new = instantiate_new_reg (x, &offset)) != 0)
4048 temp = plus_constant (new, offset);
4049 if (!validate_change (object, loc, temp, 0))
4055 temp = force_operand (temp, NULL_RTX);
4059 emit_insns_before (seq, object);
4060 if (! validate_change (object, loc, temp, 0)
4061 && ! validate_replace_rtx (x, temp, object))
4069 if (GET_CODE (XEXP (x, 0)) == REG)
4072 else if (GET_CODE (XEXP (x, 0)) == MEM)
4074 /* If we have a (addressof (mem ..)), do any instantiation inside
4075 since we know we'll be making the inside valid when we finally
4076 remove the ADDRESSOF. */
4077 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4086 /* Scan all subexpressions. */
4087 fmt = GET_RTX_FORMAT (code);
4088 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4091 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4094 else if (*fmt == 'E')
4095 for (j = 0; j < XVECLEN (x, i); j++)
4096 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4103 /* Optimization: assuming this function does not receive nonlocal gotos,
4104 delete the handlers for such, as well as the insns to establish
4105 and disestablish them. */
4111 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4113 /* Delete the handler by turning off the flag that would
4114 prevent jump_optimize from deleting it.
4115 Also permit deletion of the nonlocal labels themselves
4116 if nothing local refers to them. */
4117 if (GET_CODE (insn) == CODE_LABEL)
4121 LABEL_PRESERVE_P (insn) = 0;
4123 /* Remove it from the nonlocal_label list, to avoid confusing
4125 for (t = nonlocal_labels, last_t = 0; t;
4126 last_t = t, t = TREE_CHAIN (t))
4127 if (DECL_RTL (TREE_VALUE (t)) == insn)
4132 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4134 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4137 if (GET_CODE (insn) == INSN)
4141 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4142 if (reg_mentioned_p (t, PATTERN (insn)))
4148 || (nonlocal_goto_stack_level != 0
4149 && reg_mentioned_p (nonlocal_goto_stack_level,
4151 delete_related_insns (insn);
4159 return max_parm_reg;
4162 /* Return the first insn following those generated by `assign_parms'. */
4165 get_first_nonparm_insn ()
4168 return NEXT_INSN (last_parm_insn);
4169 return get_insns ();
4172 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4173 Crash if there is none. */
4176 get_first_block_beg ()
4179 rtx insn = get_first_nonparm_insn ();
4181 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4182 if (GET_CODE (searcher) == NOTE
4183 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4186 abort (); /* Invalid call to this function. (See comments above.) */
4190 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4191 This means a type for which function calls must pass an address to the
4192 function or get an address back from the function.
4193 EXP may be a type node or an expression (whose type is tested). */
4196 aggregate_value_p (exp)
4199 int i, regno, nregs;
4202 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4204 if (TREE_CODE (type) == VOID_TYPE)
4206 if (RETURN_IN_MEMORY (type))
4208 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4209 and thus can't be returned in registers. */
4210 if (TREE_ADDRESSABLE (type))
4212 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4214 /* Make sure we have suitable call-clobbered regs to return
4215 the value in; if not, we must return it in memory. */
4216 reg = hard_function_value (type, 0, 0);
4218 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4220 if (GET_CODE (reg) != REG)
4223 regno = REGNO (reg);
4224 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4225 for (i = 0; i < nregs; i++)
4226 if (! call_used_regs[regno + i])
4231 /* Assign RTL expressions to the function's parameters.
4232 This may involve copying them into registers and using
4233 those registers as the RTL for them. */
4236 assign_parms (fndecl)
4242 CUMULATIVE_ARGS args_so_far;
4243 enum machine_mode promoted_mode, passed_mode;
4244 enum machine_mode nominal_mode, promoted_nominal_mode;
4246 /* Total space needed so far for args on the stack,
4247 given as a constant and a tree-expression. */
4248 struct args_size stack_args_size;
4249 tree fntype = TREE_TYPE (fndecl);
4250 tree fnargs = DECL_ARGUMENTS (fndecl);
4251 /* This is used for the arg pointer when referring to stack args. */
4252 rtx internal_arg_pointer;
4253 /* This is a dummy PARM_DECL that we used for the function result if
4254 the function returns a structure. */
4255 tree function_result_decl = 0;
4256 #ifdef SETUP_INCOMING_VARARGS
4257 int varargs_setup = 0;
4259 rtx conversion_insns = 0;
4260 struct args_size alignment_pad;
4262 /* Nonzero if the last arg is named `__builtin_va_alist',
4263 which is used on some machines for old-fashioned non-ANSI varargs.h;
4264 this should be stuck onto the stack as if it had arrived there. */
4266 = (current_function_varargs
4268 && (parm = tree_last (fnargs)) != 0
4270 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4271 "__builtin_va_alist")));
4273 /* Nonzero if function takes extra anonymous args.
4274 This means the last named arg must be on the stack
4275 right before the anonymous ones. */
4277 = (TYPE_ARG_TYPES (fntype) != 0
4278 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4279 != void_type_node));
4281 current_function_stdarg = stdarg;
4283 /* If the reg that the virtual arg pointer will be translated into is
4284 not a fixed reg or is the stack pointer, make a copy of the virtual
4285 arg pointer, and address parms via the copy. The frame pointer is
4286 considered fixed even though it is not marked as such.
4288 The second time through, simply use ap to avoid generating rtx. */
4290 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4291 || ! (fixed_regs[ARG_POINTER_REGNUM]
4292 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4293 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4295 internal_arg_pointer = virtual_incoming_args_rtx;
4296 current_function_internal_arg_pointer = internal_arg_pointer;
4298 stack_args_size.constant = 0;
4299 stack_args_size.var = 0;
4301 /* If struct value address is treated as the first argument, make it so. */
4302 if (aggregate_value_p (DECL_RESULT (fndecl))
4303 && ! current_function_returns_pcc_struct
4304 && struct_value_incoming_rtx == 0)
4306 tree type = build_pointer_type (TREE_TYPE (fntype));
4308 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4310 DECL_ARG_TYPE (function_result_decl) = type;
4311 TREE_CHAIN (function_result_decl) = fnargs;
4312 fnargs = function_result_decl;
4315 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4316 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4318 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4319 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4321 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4324 /* We haven't yet found an argument that we must push and pretend the
4326 current_function_pretend_args_size = 0;
4328 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4330 struct args_size stack_offset;
4331 struct args_size arg_size;
4332 int passed_pointer = 0;
4333 int did_conversion = 0;
4334 tree passed_type = DECL_ARG_TYPE (parm);
4335 tree nominal_type = TREE_TYPE (parm);
4337 int last_named = 0, named_arg;
4339 /* Set LAST_NAMED if this is last named arg before last
4341 if (stdarg || current_function_varargs)
4345 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4346 if (DECL_NAME (tem))
4352 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4353 most machines, if this is a varargs/stdarg function, then we treat
4354 the last named arg as if it were anonymous too. */
4355 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4357 if (TREE_TYPE (parm) == error_mark_node
4358 /* This can happen after weird syntax errors
4359 or if an enum type is defined among the parms. */
4360 || TREE_CODE (parm) != PARM_DECL
4361 || passed_type == NULL)
4363 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4364 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4365 TREE_USED (parm) = 1;
4369 /* For varargs.h function, save info about regs and stack space
4370 used by the individual args, not including the va_alist arg. */
4371 if (hide_last_arg && last_named)
4372 current_function_args_info = args_so_far;
4374 /* Find mode of arg as it is passed, and mode of arg
4375 as it should be during execution of this function. */
4376 passed_mode = TYPE_MODE (passed_type);
4377 nominal_mode = TYPE_MODE (nominal_type);
4379 /* If the parm's mode is VOID, its value doesn't matter,
4380 and avoid the usual things like emit_move_insn that could crash. */
4381 if (nominal_mode == VOIDmode)
4383 SET_DECL_RTL (parm, const0_rtx);
4384 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4388 /* If the parm is to be passed as a transparent union, use the
4389 type of the first field for the tests below. We have already
4390 verified that the modes are the same. */
4391 if (DECL_TRANSPARENT_UNION (parm)
4392 || (TREE_CODE (passed_type) == UNION_TYPE
4393 && TYPE_TRANSPARENT_UNION (passed_type)))
4394 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4396 /* See if this arg was passed by invisible reference. It is if
4397 it is an object whose size depends on the contents of the
4398 object itself or if the machine requires these objects be passed
4401 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4402 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4403 || TREE_ADDRESSABLE (passed_type)
4404 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4405 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4406 passed_type, named_arg)
4410 passed_type = nominal_type = build_pointer_type (passed_type);
4412 passed_mode = nominal_mode = Pmode;
4415 promoted_mode = passed_mode;
4417 #ifdef PROMOTE_FUNCTION_ARGS
4418 /* Compute the mode in which the arg is actually extended to. */
4419 unsignedp = TREE_UNSIGNED (passed_type);
4420 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4423 /* Let machine desc say which reg (if any) the parm arrives in.
4424 0 means it arrives on the stack. */
4425 #ifdef FUNCTION_INCOMING_ARG
4426 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4427 passed_type, named_arg);
4429 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4430 passed_type, named_arg);
4433 if (entry_parm == 0)
4434 promoted_mode = passed_mode;
4436 #ifdef SETUP_INCOMING_VARARGS
4437 /* If this is the last named parameter, do any required setup for
4438 varargs or stdargs. We need to know about the case of this being an
4439 addressable type, in which case we skip the registers it
4440 would have arrived in.
4442 For stdargs, LAST_NAMED will be set for two parameters, the one that
4443 is actually the last named, and the dummy parameter. We only
4444 want to do this action once.
4446 Also, indicate when RTL generation is to be suppressed. */
4447 if (last_named && !varargs_setup)
4449 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4450 current_function_pretend_args_size, 0);
4455 /* Determine parm's home in the stack,
4456 in case it arrives in the stack or we should pretend it did.
4458 Compute the stack position and rtx where the argument arrives
4461 There is one complexity here: If this was a parameter that would
4462 have been passed in registers, but wasn't only because it is
4463 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4464 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4465 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4466 0 as it was the previous time. */
4468 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4469 locate_and_pad_parm (promoted_mode, passed_type,
4470 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4473 #ifdef FUNCTION_INCOMING_ARG
4474 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4476 pretend_named) != 0,
4478 FUNCTION_ARG (args_so_far, promoted_mode,
4480 pretend_named) != 0,
4483 fndecl, &stack_args_size, &stack_offset, &arg_size,
4487 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4489 if (offset_rtx == const0_rtx)
4490 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4492 stack_parm = gen_rtx_MEM (promoted_mode,
4493 gen_rtx_PLUS (Pmode,
4494 internal_arg_pointer,
4497 set_mem_attributes (stack_parm, parm, 1);
4500 /* If this parameter was passed both in registers and in the stack,
4501 use the copy on the stack. */
4502 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4505 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4506 /* If this parm was passed part in regs and part in memory,
4507 pretend it arrived entirely in memory
4508 by pushing the register-part onto the stack.
4510 In the special case of a DImode or DFmode that is split,
4511 we could put it together in a pseudoreg directly,
4512 but for now that's not worth bothering with. */
4516 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4517 passed_type, named_arg);
4521 current_function_pretend_args_size
4522 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4523 / (PARM_BOUNDARY / BITS_PER_UNIT)
4524 * (PARM_BOUNDARY / BITS_PER_UNIT));
4526 /* Handle calls that pass values in multiple non-contiguous
4527 locations. The Irix 6 ABI has examples of this. */
4528 if (GET_CODE (entry_parm) == PARALLEL)
4529 emit_group_store (validize_mem (stack_parm), entry_parm,
4530 int_size_in_bytes (TREE_TYPE (parm)));
4533 move_block_from_reg (REGNO (entry_parm),
4534 validize_mem (stack_parm), nregs,
4535 int_size_in_bytes (TREE_TYPE (parm)));
4537 entry_parm = stack_parm;
4542 /* If we didn't decide this parm came in a register,
4543 by default it came on the stack. */
4544 if (entry_parm == 0)
4545 entry_parm = stack_parm;
4547 /* Record permanently how this parm was passed. */
4548 DECL_INCOMING_RTL (parm) = entry_parm;
4550 /* If there is actually space on the stack for this parm,
4551 count it in stack_args_size; otherwise set stack_parm to 0
4552 to indicate there is no preallocated stack slot for the parm. */
4554 if (entry_parm == stack_parm
4555 || (GET_CODE (entry_parm) == PARALLEL
4556 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4557 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4558 /* On some machines, even if a parm value arrives in a register
4559 there is still an (uninitialized) stack slot allocated for it.
4561 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4562 whether this parameter already has a stack slot allocated,
4563 because an arg block exists only if current_function_args_size
4564 is larger than some threshold, and we haven't calculated that
4565 yet. So, for now, we just assume that stack slots never exist
4567 || REG_PARM_STACK_SPACE (fndecl) > 0
4571 stack_args_size.constant += arg_size.constant;
4573 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4576 /* No stack slot was pushed for this parm. */
4579 /* Update info on where next arg arrives in registers. */
4581 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4582 passed_type, named_arg);
4584 /* If we can't trust the parm stack slot to be aligned enough
4585 for its ultimate type, don't use that slot after entry.
4586 We'll make another stack slot, if we need one. */
4588 unsigned int thisparm_boundary
4589 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4591 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4595 /* If parm was passed in memory, and we need to convert it on entry,
4596 don't store it back in that same slot. */
4598 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4601 /* When an argument is passed in multiple locations, we can't
4602 make use of this information, but we can save some copying if
4603 the whole argument is passed in a single register. */
4604 if (GET_CODE (entry_parm) == PARALLEL
4605 && nominal_mode != BLKmode && passed_mode != BLKmode)
4607 int i, len = XVECLEN (entry_parm, 0);
4609 for (i = 0; i < len; i++)
4610 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4611 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4612 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4614 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4616 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4617 DECL_INCOMING_RTL (parm) = entry_parm;
4622 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4623 in the mode in which it arrives.
4624 STACK_PARM is an RTX for a stack slot where the parameter can live
4625 during the function (in case we want to put it there).
4626 STACK_PARM is 0 if no stack slot was pushed for it.
4628 Now output code if necessary to convert ENTRY_PARM to
4629 the type in which this function declares it,
4630 and store that result in an appropriate place,
4631 which may be a pseudo reg, may be STACK_PARM,
4632 or may be a local stack slot if STACK_PARM is 0.
4634 Set DECL_RTL to that place. */
4636 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4638 /* If a BLKmode arrives in registers, copy it to a stack slot.
4639 Handle calls that pass values in multiple non-contiguous
4640 locations. The Irix 6 ABI has examples of this. */
4641 if (GET_CODE (entry_parm) == REG
4642 || GET_CODE (entry_parm) == PARALLEL)
4645 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4648 /* Note that we will be storing an integral number of words.
4649 So we have to be careful to ensure that we allocate an
4650 integral number of words. We do this below in the
4651 assign_stack_local if space was not allocated in the argument
4652 list. If it was, this will not work if PARM_BOUNDARY is not
4653 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4654 if it becomes a problem. */
4656 if (stack_parm == 0)
4659 = assign_stack_local (GET_MODE (entry_parm),
4661 set_mem_attributes (stack_parm, parm, 1);
4664 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4667 /* Handle calls that pass values in multiple non-contiguous
4668 locations. The Irix 6 ABI has examples of this. */
4669 if (GET_CODE (entry_parm) == PARALLEL)
4670 emit_group_store (validize_mem (stack_parm), entry_parm,
4671 int_size_in_bytes (TREE_TYPE (parm)));
4673 move_block_from_reg (REGNO (entry_parm),
4674 validize_mem (stack_parm),
4675 size_stored / UNITS_PER_WORD,
4676 int_size_in_bytes (TREE_TYPE (parm)));
4678 SET_DECL_RTL (parm, stack_parm);
4680 else if (! ((! optimize
4681 && ! DECL_REGISTER (parm))
4682 || TREE_SIDE_EFFECTS (parm)
4683 /* If -ffloat-store specified, don't put explicit
4684 float variables into registers. */
4685 || (flag_float_store
4686 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4687 /* Always assign pseudo to structure return or item passed
4688 by invisible reference. */
4689 || passed_pointer || parm == function_result_decl)
4691 /* Store the parm in a pseudoregister during the function, but we
4692 may need to do it in a wider mode. */
4695 unsigned int regno, regnoi = 0, regnor = 0;
4697 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4699 promoted_nominal_mode
4700 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4702 parmreg = gen_reg_rtx (promoted_nominal_mode);
4703 mark_user_reg (parmreg);
4705 /* If this was an item that we received a pointer to, set DECL_RTL
4709 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4711 set_mem_attributes (x, parm, 1);
4712 SET_DECL_RTL (parm, x);
4716 SET_DECL_RTL (parm, parmreg);
4717 maybe_set_unchanging (DECL_RTL (parm), parm);
4720 /* Copy the value into the register. */
4721 if (nominal_mode != passed_mode
4722 || promoted_nominal_mode != promoted_mode)
4725 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4726 mode, by the caller. We now have to convert it to
4727 NOMINAL_MODE, if different. However, PARMREG may be in
4728 a different mode than NOMINAL_MODE if it is being stored
4731 If ENTRY_PARM is a hard register, it might be in a register
4732 not valid for operating in its mode (e.g., an odd-numbered
4733 register for a DFmode). In that case, moves are the only
4734 thing valid, so we can't do a convert from there. This
4735 occurs when the calling sequence allow such misaligned
4738 In addition, the conversion may involve a call, which could
4739 clobber parameters which haven't been copied to pseudo
4740 registers yet. Therefore, we must first copy the parm to
4741 a pseudo reg here, and save the conversion until after all
4742 parameters have been moved. */
4744 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4746 emit_move_insn (tempreg, validize_mem (entry_parm));
4748 push_to_sequence (conversion_insns);
4749 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4751 if (GET_CODE (tempreg) == SUBREG
4752 && GET_MODE (tempreg) == nominal_mode
4753 && GET_CODE (SUBREG_REG (tempreg)) == REG
4754 && nominal_mode == passed_mode
4755 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4756 && GET_MODE_SIZE (GET_MODE (tempreg))
4757 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4759 /* The argument is already sign/zero extended, so note it
4761 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4762 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4765 /* TREE_USED gets set erroneously during expand_assignment. */
4766 save_tree_used = TREE_USED (parm);
4767 expand_assignment (parm,
4768 make_tree (nominal_type, tempreg), 0, 0);
4769 TREE_USED (parm) = save_tree_used;
4770 conversion_insns = get_insns ();
4775 emit_move_insn (parmreg, validize_mem (entry_parm));
4777 /* If we were passed a pointer but the actual value
4778 can safely live in a register, put it in one. */
4779 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4780 /* If by-reference argument was promoted, demote it. */
4781 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4783 && ! DECL_REGISTER (parm))
4784 || TREE_SIDE_EFFECTS (parm)
4785 /* If -ffloat-store specified, don't put explicit
4786 float variables into registers. */
4787 || (flag_float_store
4788 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4790 /* We can't use nominal_mode, because it will have been set to
4791 Pmode above. We must use the actual mode of the parm. */
4792 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4793 mark_user_reg (parmreg);
4794 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4796 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4797 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4798 push_to_sequence (conversion_insns);
4799 emit_move_insn (tempreg, DECL_RTL (parm));
4801 convert_to_mode (GET_MODE (parmreg),
4804 emit_move_insn (parmreg, DECL_RTL (parm));
4805 conversion_insns = get_insns();
4810 emit_move_insn (parmreg, DECL_RTL (parm));
4811 SET_DECL_RTL (parm, parmreg);
4812 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4816 #ifdef FUNCTION_ARG_CALLEE_COPIES
4817 /* If we are passed an arg by reference and it is our responsibility
4818 to make a copy, do it now.
4819 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4820 original argument, so we must recreate them in the call to
4821 FUNCTION_ARG_CALLEE_COPIES. */
4822 /* ??? Later add code to handle the case that if the argument isn't
4823 modified, don't do the copy. */
4825 else if (passed_pointer
4826 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4827 TYPE_MODE (DECL_ARG_TYPE (parm)),
4828 DECL_ARG_TYPE (parm),
4830 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4833 tree type = DECL_ARG_TYPE (parm);
4835 /* This sequence may involve a library call perhaps clobbering
4836 registers that haven't been copied to pseudos yet. */
4838 push_to_sequence (conversion_insns);
4840 if (!COMPLETE_TYPE_P (type)
4841 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4842 /* This is a variable sized object. */
4843 copy = gen_rtx_MEM (BLKmode,
4844 allocate_dynamic_stack_space
4845 (expr_size (parm), NULL_RTX,
4846 TYPE_ALIGN (type)));
4848 copy = assign_stack_temp (TYPE_MODE (type),
4849 int_size_in_bytes (type), 1);
4850 set_mem_attributes (copy, parm, 1);
4852 store_expr (parm, copy, 0);
4853 emit_move_insn (parmreg, XEXP (copy, 0));
4854 conversion_insns = get_insns ();
4858 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4860 /* In any case, record the parm's desired stack location
4861 in case we later discover it must live in the stack.
4863 If it is a COMPLEX value, store the stack location for both
4866 if (GET_CODE (parmreg) == CONCAT)
4867 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4869 regno = REGNO (parmreg);
4871 if (regno >= max_parm_reg)
4874 int old_max_parm_reg = max_parm_reg;
4876 /* It's slow to expand this one register at a time,
4877 but it's also rare and we need max_parm_reg to be
4878 precisely correct. */
4879 max_parm_reg = regno + 1;
4880 new = (rtx *) xrealloc (parm_reg_stack_loc,
4881 max_parm_reg * sizeof (rtx));
4882 memset ((char *) (new + old_max_parm_reg), 0,
4883 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4884 parm_reg_stack_loc = new;
4887 if (GET_CODE (parmreg) == CONCAT)
4889 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4891 regnor = REGNO (gen_realpart (submode, parmreg));
4892 regnoi = REGNO (gen_imagpart (submode, parmreg));
4894 if (stack_parm != 0)
4896 parm_reg_stack_loc[regnor]
4897 = gen_realpart (submode, stack_parm);
4898 parm_reg_stack_loc[regnoi]
4899 = gen_imagpart (submode, stack_parm);
4903 parm_reg_stack_loc[regnor] = 0;
4904 parm_reg_stack_loc[regnoi] = 0;
4908 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4910 /* Mark the register as eliminable if we did no conversion
4911 and it was copied from memory at a fixed offset,
4912 and the arg pointer was not copied to a pseudo-reg.
4913 If the arg pointer is a pseudo reg or the offset formed
4914 an invalid address, such memory-equivalences
4915 as we make here would screw up life analysis for it. */
4916 if (nominal_mode == passed_mode
4919 && GET_CODE (stack_parm) == MEM
4920 && stack_offset.var == 0
4921 && reg_mentioned_p (virtual_incoming_args_rtx,
4922 XEXP (stack_parm, 0)))
4924 rtx linsn = get_last_insn ();
4927 /* Mark complex types separately. */
4928 if (GET_CODE (parmreg) == CONCAT)
4929 /* Scan backwards for the set of the real and
4931 for (sinsn = linsn; sinsn != 0;
4932 sinsn = prev_nonnote_insn (sinsn))
4934 set = single_set (sinsn);
4936 && SET_DEST (set) == regno_reg_rtx [regnoi])
4938 = gen_rtx_EXPR_LIST (REG_EQUIV,
4939 parm_reg_stack_loc[regnoi],
4942 && SET_DEST (set) == regno_reg_rtx [regnor])
4944 = gen_rtx_EXPR_LIST (REG_EQUIV,
4945 parm_reg_stack_loc[regnor],
4948 else if ((set = single_set (linsn)) != 0
4949 && SET_DEST (set) == parmreg)
4951 = gen_rtx_EXPR_LIST (REG_EQUIV,
4952 stack_parm, REG_NOTES (linsn));
4955 /* For pointer data type, suggest pointer register. */
4956 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4957 mark_reg_pointer (parmreg,
4958 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4960 /* If something wants our address, try to use ADDRESSOF. */
4961 if (TREE_ADDRESSABLE (parm))
4963 /* If we end up putting something into the stack,
4964 fixup_var_refs_insns will need to make a pass over
4965 all the instructions. It looks through the pending
4966 sequences -- but it can't see the ones in the
4967 CONVERSION_INSNS, if they're not on the sequence
4968 stack. So, we go back to that sequence, just so that
4969 the fixups will happen. */
4970 push_to_sequence (conversion_insns);
4971 put_var_into_stack (parm);
4972 conversion_insns = get_insns ();
4978 /* Value must be stored in the stack slot STACK_PARM
4979 during function execution. */
4981 if (promoted_mode != nominal_mode)
4983 /* Conversion is required. */
4984 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4986 emit_move_insn (tempreg, validize_mem (entry_parm));
4988 push_to_sequence (conversion_insns);
4989 entry_parm = convert_to_mode (nominal_mode, tempreg,
4990 TREE_UNSIGNED (TREE_TYPE (parm)));
4992 /* ??? This may need a big-endian conversion on sparc64. */
4993 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4995 conversion_insns = get_insns ();
5000 if (entry_parm != stack_parm)
5002 if (stack_parm == 0)
5005 = assign_stack_local (GET_MODE (entry_parm),
5006 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5007 set_mem_attributes (stack_parm, parm, 1);
5010 if (promoted_mode != nominal_mode)
5012 push_to_sequence (conversion_insns);
5013 emit_move_insn (validize_mem (stack_parm),
5014 validize_mem (entry_parm));
5015 conversion_insns = get_insns ();
5019 emit_move_insn (validize_mem (stack_parm),
5020 validize_mem (entry_parm));
5023 SET_DECL_RTL (parm, stack_parm);
5026 /* If this "parameter" was the place where we are receiving the
5027 function's incoming structure pointer, set up the result. */
5028 if (parm == function_result_decl)
5030 tree result = DECL_RESULT (fndecl);
5031 rtx addr = DECL_RTL (parm);
5034 #ifdef POINTERS_EXTEND_UNSIGNED
5035 if (GET_MODE (addr) != Pmode)
5036 addr = convert_memory_address (Pmode, addr);
5039 x = gen_rtx_MEM (DECL_MODE (result), addr);
5040 set_mem_attributes (x, result, 1);
5041 SET_DECL_RTL (result, x);
5044 if (GET_CODE (DECL_RTL (parm)) == REG)
5045 REGNO_DECL (REGNO (DECL_RTL (parm))) = parm;
5046 else if (GET_CODE (DECL_RTL (parm)) == CONCAT)
5048 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 0))) = parm;
5049 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 1))) = parm;
5054 /* Output all parameter conversion instructions (possibly including calls)
5055 now that all parameters have been copied out of hard registers. */
5056 emit_insns (conversion_insns);
5058 last_parm_insn = get_last_insn ();
5060 current_function_args_size = stack_args_size.constant;
5062 /* Adjust function incoming argument size for alignment and
5065 #ifdef REG_PARM_STACK_SPACE
5066 #ifndef MAYBE_REG_PARM_STACK_SPACE
5067 current_function_args_size = MAX (current_function_args_size,
5068 REG_PARM_STACK_SPACE (fndecl));
5072 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5074 current_function_args_size
5075 = ((current_function_args_size + STACK_BYTES - 1)
5076 / STACK_BYTES) * STACK_BYTES;
5078 #ifdef ARGS_GROW_DOWNWARD
5079 current_function_arg_offset_rtx
5080 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5081 : expand_expr (size_diffop (stack_args_size.var,
5082 size_int (-stack_args_size.constant)),
5083 NULL_RTX, VOIDmode, 0));
5085 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5088 /* See how many bytes, if any, of its args a function should try to pop
5091 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5092 current_function_args_size);
5094 /* For stdarg.h function, save info about
5095 regs and stack space used by the named args. */
5098 current_function_args_info = args_so_far;
5100 /* Set the rtx used for the function return value. Put this in its
5101 own variable so any optimizers that need this information don't have
5102 to include tree.h. Do this here so it gets done when an inlined
5103 function gets output. */
5105 current_function_return_rtx
5106 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5107 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5110 /* Indicate whether REGNO is an incoming argument to the current function
5111 that was promoted to a wider mode. If so, return the RTX for the
5112 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5113 that REGNO is promoted from and whether the promotion was signed or
5116 #ifdef PROMOTE_FUNCTION_ARGS
5119 promoted_input_arg (regno, pmode, punsignedp)
5121 enum machine_mode *pmode;
5126 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5127 arg = TREE_CHAIN (arg))
5128 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5129 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5130 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5132 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5133 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5135 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5136 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5137 && mode != DECL_MODE (arg))
5139 *pmode = DECL_MODE (arg);
5140 *punsignedp = unsignedp;
5141 return DECL_INCOMING_RTL (arg);
5150 /* Compute the size and offset from the start of the stacked arguments for a
5151 parm passed in mode PASSED_MODE and with type TYPE.
5153 INITIAL_OFFSET_PTR points to the current offset into the stacked
5156 The starting offset and size for this parm are returned in *OFFSET_PTR
5157 and *ARG_SIZE_PTR, respectively.
5159 IN_REGS is non-zero if the argument will be passed in registers. It will
5160 never be set if REG_PARM_STACK_SPACE is not defined.
5162 FNDECL is the function in which the argument was defined.
5164 There are two types of rounding that are done. The first, controlled by
5165 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5166 list to be aligned to the specific boundary (in bits). This rounding
5167 affects the initial and starting offsets, but not the argument size.
5169 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5170 optionally rounds the size of the parm to PARM_BOUNDARY. The
5171 initial offset is not affected by this rounding, while the size always
5172 is and the starting offset may be. */
5174 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5175 initial_offset_ptr is positive because locate_and_pad_parm's
5176 callers pass in the total size of args so far as
5177 initial_offset_ptr. arg_size_ptr is always positive. */
5180 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5181 initial_offset_ptr, offset_ptr, arg_size_ptr,
5183 enum machine_mode passed_mode;
5185 int in_regs ATTRIBUTE_UNUSED;
5186 tree fndecl ATTRIBUTE_UNUSED;
5187 struct args_size *initial_offset_ptr;
5188 struct args_size *offset_ptr;
5189 struct args_size *arg_size_ptr;
5190 struct args_size *alignment_pad;
5194 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5195 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5196 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5198 #ifdef REG_PARM_STACK_SPACE
5199 /* If we have found a stack parm before we reach the end of the
5200 area reserved for registers, skip that area. */
5203 int reg_parm_stack_space = 0;
5205 #ifdef MAYBE_REG_PARM_STACK_SPACE
5206 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5208 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5210 if (reg_parm_stack_space > 0)
5212 if (initial_offset_ptr->var)
5214 initial_offset_ptr->var
5215 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5216 ssize_int (reg_parm_stack_space));
5217 initial_offset_ptr->constant = 0;
5219 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5220 initial_offset_ptr->constant = reg_parm_stack_space;
5223 #endif /* REG_PARM_STACK_SPACE */
5225 arg_size_ptr->var = 0;
5226 arg_size_ptr->constant = 0;
5227 alignment_pad->var = 0;
5228 alignment_pad->constant = 0;
5230 #ifdef ARGS_GROW_DOWNWARD
5231 if (initial_offset_ptr->var)
5233 offset_ptr->constant = 0;
5234 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5235 initial_offset_ptr->var);
5239 offset_ptr->constant = -initial_offset_ptr->constant;
5240 offset_ptr->var = 0;
5242 if (where_pad != none
5243 && (!host_integerp (sizetree, 1)
5244 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5245 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5246 SUB_PARM_SIZE (*offset_ptr, sizetree);
5247 if (where_pad != downward)
5248 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5249 if (initial_offset_ptr->var)
5250 arg_size_ptr->var = size_binop (MINUS_EXPR,
5251 size_binop (MINUS_EXPR,
5253 initial_offset_ptr->var),
5257 arg_size_ptr->constant = (-initial_offset_ptr->constant
5258 - offset_ptr->constant);
5260 #else /* !ARGS_GROW_DOWNWARD */
5262 #ifdef REG_PARM_STACK_SPACE
5263 || REG_PARM_STACK_SPACE (fndecl) > 0
5266 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5267 *offset_ptr = *initial_offset_ptr;
5269 #ifdef PUSH_ROUNDING
5270 if (passed_mode != BLKmode)
5271 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5274 /* Pad_below needs the pre-rounded size to know how much to pad below
5275 so this must be done before rounding up. */
5276 if (where_pad == downward
5277 /* However, BLKmode args passed in regs have their padding done elsewhere.
5278 The stack slot must be able to hold the entire register. */
5279 && !(in_regs && passed_mode == BLKmode))
5280 pad_below (offset_ptr, passed_mode, sizetree);
5282 if (where_pad != none
5283 && (!host_integerp (sizetree, 1)
5284 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5285 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5287 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5288 #endif /* ARGS_GROW_DOWNWARD */
5291 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5292 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5295 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5296 struct args_size *offset_ptr;
5298 struct args_size *alignment_pad;
5300 tree save_var = NULL_TREE;
5301 HOST_WIDE_INT save_constant = 0;
5303 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5305 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5307 save_var = offset_ptr->var;
5308 save_constant = offset_ptr->constant;
5311 alignment_pad->var = NULL_TREE;
5312 alignment_pad->constant = 0;
5314 if (boundary > BITS_PER_UNIT)
5316 if (offset_ptr->var)
5319 #ifdef ARGS_GROW_DOWNWARD
5324 (ARGS_SIZE_TREE (*offset_ptr),
5325 boundary / BITS_PER_UNIT);
5326 offset_ptr->constant = 0; /*?*/
5327 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5328 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5333 offset_ptr->constant =
5334 #ifdef ARGS_GROW_DOWNWARD
5335 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5337 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5339 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5340 alignment_pad->constant = offset_ptr->constant - save_constant;
5345 #ifndef ARGS_GROW_DOWNWARD
5347 pad_below (offset_ptr, passed_mode, sizetree)
5348 struct args_size *offset_ptr;
5349 enum machine_mode passed_mode;
5352 if (passed_mode != BLKmode)
5354 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5355 offset_ptr->constant
5356 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5357 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5358 - GET_MODE_SIZE (passed_mode));
5362 if (TREE_CODE (sizetree) != INTEGER_CST
5363 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5365 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5366 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5368 ADD_PARM_SIZE (*offset_ptr, s2);
5369 SUB_PARM_SIZE (*offset_ptr, sizetree);
5375 /* Walk the tree of blocks describing the binding levels within a function
5376 and warn about uninitialized variables.
5377 This is done after calling flow_analysis and before global_alloc
5378 clobbers the pseudo-regs to hard regs. */
5381 uninitialized_vars_warning (block)
5385 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5387 if (warn_uninitialized
5388 && TREE_CODE (decl) == VAR_DECL
5389 /* These warnings are unreliable for and aggregates
5390 because assigning the fields one by one can fail to convince
5391 flow.c that the entire aggregate was initialized.
5392 Unions are troublesome because members may be shorter. */
5393 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5394 && DECL_RTL (decl) != 0
5395 && GET_CODE (DECL_RTL (decl)) == REG
5396 /* Global optimizations can make it difficult to determine if a
5397 particular variable has been initialized. However, a VAR_DECL
5398 with a nonzero DECL_INITIAL had an initializer, so do not
5399 claim it is potentially uninitialized.
5401 We do not care about the actual value in DECL_INITIAL, so we do
5402 not worry that it may be a dangling pointer. */
5403 && DECL_INITIAL (decl) == NULL_TREE
5404 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5405 warning_with_decl (decl,
5406 "`%s' might be used uninitialized in this function");
5408 && TREE_CODE (decl) == VAR_DECL
5409 && DECL_RTL (decl) != 0
5410 && GET_CODE (DECL_RTL (decl)) == REG
5411 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5412 warning_with_decl (decl,
5413 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5415 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5416 uninitialized_vars_warning (sub);
5419 /* Do the appropriate part of uninitialized_vars_warning
5420 but for arguments instead of local variables. */
5423 setjmp_args_warning ()
5426 for (decl = DECL_ARGUMENTS (current_function_decl);
5427 decl; decl = TREE_CHAIN (decl))
5428 if (DECL_RTL (decl) != 0
5429 && GET_CODE (DECL_RTL (decl)) == REG
5430 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5431 warning_with_decl (decl,
5432 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5435 /* If this function call setjmp, put all vars into the stack
5436 unless they were declared `register'. */
5439 setjmp_protect (block)
5443 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5444 if ((TREE_CODE (decl) == VAR_DECL
5445 || TREE_CODE (decl) == PARM_DECL)
5446 && DECL_RTL (decl) != 0
5447 && (GET_CODE (DECL_RTL (decl)) == REG
5448 || (GET_CODE (DECL_RTL (decl)) == MEM
5449 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5450 /* If this variable came from an inline function, it must be
5451 that its life doesn't overlap the setjmp. If there was a
5452 setjmp in the function, it would already be in memory. We
5453 must exclude such variable because their DECL_RTL might be
5454 set to strange things such as virtual_stack_vars_rtx. */
5455 && ! DECL_FROM_INLINE (decl)
5457 #ifdef NON_SAVING_SETJMP
5458 /* If longjmp doesn't restore the registers,
5459 don't put anything in them. */
5463 ! DECL_REGISTER (decl)))
5464 put_var_into_stack (decl);
5465 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5466 setjmp_protect (sub);
5469 /* Like the previous function, but for args instead of local variables. */
5472 setjmp_protect_args ()
5475 for (decl = DECL_ARGUMENTS (current_function_decl);
5476 decl; decl = TREE_CHAIN (decl))
5477 if ((TREE_CODE (decl) == VAR_DECL
5478 || TREE_CODE (decl) == PARM_DECL)
5479 && DECL_RTL (decl) != 0
5480 && (GET_CODE (DECL_RTL (decl)) == REG
5481 || (GET_CODE (DECL_RTL (decl)) == MEM
5482 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5484 /* If longjmp doesn't restore the registers,
5485 don't put anything in them. */
5486 #ifdef NON_SAVING_SETJMP
5490 ! DECL_REGISTER (decl)))
5491 put_var_into_stack (decl);
5494 /* Return the context-pointer register corresponding to DECL,
5495 or 0 if it does not need one. */
5498 lookup_static_chain (decl)
5501 tree context = decl_function_context (decl);
5505 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5508 /* We treat inline_function_decl as an alias for the current function
5509 because that is the inline function whose vars, types, etc.
5510 are being merged into the current function.
5511 See expand_inline_function. */
5512 if (context == current_function_decl || context == inline_function_decl)
5513 return virtual_stack_vars_rtx;
5515 for (link = context_display; link; link = TREE_CHAIN (link))
5516 if (TREE_PURPOSE (link) == context)
5517 return RTL_EXPR_RTL (TREE_VALUE (link));
5522 /* Convert a stack slot address ADDR for variable VAR
5523 (from a containing function)
5524 into an address valid in this function (using a static chain). */
5527 fix_lexical_addr (addr, var)
5532 HOST_WIDE_INT displacement;
5533 tree context = decl_function_context (var);
5534 struct function *fp;
5537 /* If this is the present function, we need not do anything. */
5538 if (context == current_function_decl || context == inline_function_decl)
5541 fp = find_function_data (context);
5543 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5544 addr = XEXP (XEXP (addr, 0), 0);
5546 /* Decode given address as base reg plus displacement. */
5547 if (GET_CODE (addr) == REG)
5548 basereg = addr, displacement = 0;
5549 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5550 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5554 /* We accept vars reached via the containing function's
5555 incoming arg pointer and via its stack variables pointer. */
5556 if (basereg == fp->internal_arg_pointer)
5558 /* If reached via arg pointer, get the arg pointer value
5559 out of that function's stack frame.
5561 There are two cases: If a separate ap is needed, allocate a
5562 slot in the outer function for it and dereference it that way.
5563 This is correct even if the real ap is actually a pseudo.
5564 Otherwise, just adjust the offset from the frame pointer to
5567 #ifdef NEED_SEPARATE_AP
5570 addr = get_arg_pointer_save_area (fp);
5571 addr = fix_lexical_addr (XEXP (addr, 0), var);
5572 addr = memory_address (Pmode, addr);
5574 base = gen_rtx_MEM (Pmode, addr);
5575 set_mem_alias_set (base, get_frame_alias_set ());
5576 base = copy_to_reg (base);
5578 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5579 base = lookup_static_chain (var);
5583 else if (basereg == virtual_stack_vars_rtx)
5585 /* This is the same code as lookup_static_chain, duplicated here to
5586 avoid an extra call to decl_function_context. */
5589 for (link = context_display; link; link = TREE_CHAIN (link))
5590 if (TREE_PURPOSE (link) == context)
5592 base = RTL_EXPR_RTL (TREE_VALUE (link));
5600 /* Use same offset, relative to appropriate static chain or argument
5602 return plus_constant (base, displacement);
5605 /* Return the address of the trampoline for entering nested fn FUNCTION.
5606 If necessary, allocate a trampoline (in the stack frame)
5607 and emit rtl to initialize its contents (at entry to this function). */
5610 trampoline_address (function)
5616 struct function *fp;
5619 /* Find an existing trampoline and return it. */
5620 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5621 if (TREE_PURPOSE (link) == function)
5623 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5625 for (fp = outer_function_chain; fp; fp = fp->outer)
5626 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5627 if (TREE_PURPOSE (link) == function)
5629 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5631 return adjust_trampoline_addr (tramp);
5634 /* None exists; we must make one. */
5636 /* Find the `struct function' for the function containing FUNCTION. */
5638 fn_context = decl_function_context (function);
5639 if (fn_context != current_function_decl
5640 && fn_context != inline_function_decl)
5641 fp = find_function_data (fn_context);
5643 /* Allocate run-time space for this trampoline
5644 (usually in the defining function's stack frame). */
5645 #ifdef ALLOCATE_TRAMPOLINE
5646 tramp = ALLOCATE_TRAMPOLINE (fp);
5648 /* If rounding needed, allocate extra space
5649 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5650 #ifdef TRAMPOLINE_ALIGNMENT
5651 #define TRAMPOLINE_REAL_SIZE \
5652 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5654 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5656 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5660 /* Record the trampoline for reuse and note it for later initialization
5661 by expand_function_end. */
5664 rtlexp = make_node (RTL_EXPR);
5665 RTL_EXPR_RTL (rtlexp) = tramp;
5666 fp->x_trampoline_list = tree_cons (function, rtlexp,
5667 fp->x_trampoline_list);
5671 /* Make the RTL_EXPR node temporary, not momentary, so that the
5672 trampoline_list doesn't become garbage. */
5673 rtlexp = make_node (RTL_EXPR);
5675 RTL_EXPR_RTL (rtlexp) = tramp;
5676 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5679 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5680 return adjust_trampoline_addr (tramp);
5683 /* Given a trampoline address,
5684 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5687 round_trampoline_addr (tramp)
5690 #ifdef TRAMPOLINE_ALIGNMENT
5691 /* Round address up to desired boundary. */
5692 rtx temp = gen_reg_rtx (Pmode);
5693 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5694 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5696 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5697 temp, 0, OPTAB_LIB_WIDEN);
5698 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5699 temp, 0, OPTAB_LIB_WIDEN);
5704 /* Given a trampoline address, round it then apply any
5705 platform-specific adjustments so that the result can be used for a
5709 adjust_trampoline_addr (tramp)
5712 tramp = round_trampoline_addr (tramp);
5713 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5714 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5719 /* Put all this function's BLOCK nodes including those that are chained
5720 onto the first block into a vector, and return it.
5721 Also store in each NOTE for the beginning or end of a block
5722 the index of that block in the vector.
5723 The arguments are BLOCK, the chain of top-level blocks of the function,
5724 and INSNS, the insn chain of the function. */
5730 tree *block_vector, *last_block_vector;
5732 tree block = DECL_INITIAL (current_function_decl);
5737 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5738 depth-first order. */
5739 block_vector = get_block_vector (block, &n_blocks);
5740 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5742 last_block_vector = identify_blocks_1 (get_insns (),
5744 block_vector + n_blocks,
5747 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5748 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5749 if (0 && last_block_vector != block_vector + n_blocks)
5752 free (block_vector);
5756 /* Subroutine of identify_blocks. Do the block substitution on the
5757 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5759 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5760 BLOCK_VECTOR is incremented for each block seen. */
5763 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5766 tree *end_block_vector;
5767 tree *orig_block_stack;
5770 tree *block_stack = orig_block_stack;
5772 for (insn = insns; insn; insn = NEXT_INSN (insn))
5774 if (GET_CODE (insn) == NOTE)
5776 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5780 /* If there are more block notes than BLOCKs, something
5782 if (block_vector == end_block_vector)
5785 b = *block_vector++;
5786 NOTE_BLOCK (insn) = b;
5789 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5791 /* If there are more NOTE_INSN_BLOCK_ENDs than
5792 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5793 if (block_stack == orig_block_stack)
5796 NOTE_BLOCK (insn) = *--block_stack;
5799 else if (GET_CODE (insn) == CALL_INSN
5800 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5802 rtx cp = PATTERN (insn);
5804 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5805 end_block_vector, block_stack);
5807 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5808 end_block_vector, block_stack);
5810 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5811 end_block_vector, block_stack);
5815 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5816 something is badly wrong. */
5817 if (block_stack != orig_block_stack)
5820 return block_vector;
5823 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5824 and create duplicate blocks. */
5825 /* ??? Need an option to either create block fragments or to create
5826 abstract origin duplicates of a source block. It really depends
5827 on what optimization has been performed. */
5832 tree block = DECL_INITIAL (current_function_decl);
5833 varray_type block_stack;
5835 if (block == NULL_TREE)
5838 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5840 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5841 reorder_blocks_0 (block);
5843 /* Prune the old trees away, so that they don't get in the way. */
5844 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5845 BLOCK_CHAIN (block) = NULL_TREE;
5847 /* Recreate the block tree from the note nesting. */
5848 reorder_blocks_1 (get_insns (), block, &block_stack);
5849 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5851 /* Remove deleted blocks from the block fragment chains. */
5852 reorder_fix_fragments (block);
5854 VARRAY_FREE (block_stack);
5857 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5860 reorder_blocks_0 (block)
5865 TREE_ASM_WRITTEN (block) = 0;
5866 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5867 block = BLOCK_CHAIN (block);
5872 reorder_blocks_1 (insns, current_block, p_block_stack)
5875 varray_type *p_block_stack;
5879 for (insn = insns; insn; insn = NEXT_INSN (insn))
5881 if (GET_CODE (insn) == NOTE)
5883 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5885 tree block = NOTE_BLOCK (insn);
5887 /* If we have seen this block before, that means it now
5888 spans multiple address regions. Create a new fragment. */
5889 if (TREE_ASM_WRITTEN (block))
5891 tree new_block = copy_node (block);
5894 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5895 ? BLOCK_FRAGMENT_ORIGIN (block)
5897 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5898 BLOCK_FRAGMENT_CHAIN (new_block)
5899 = BLOCK_FRAGMENT_CHAIN (origin);
5900 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5902 NOTE_BLOCK (insn) = new_block;
5906 BLOCK_SUBBLOCKS (block) = 0;
5907 TREE_ASM_WRITTEN (block) = 1;
5908 BLOCK_SUPERCONTEXT (block) = current_block;
5909 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5910 BLOCK_SUBBLOCKS (current_block) = block;
5911 current_block = block;
5912 VARRAY_PUSH_TREE (*p_block_stack, block);
5914 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5916 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5917 VARRAY_POP (*p_block_stack);
5918 BLOCK_SUBBLOCKS (current_block)
5919 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5920 current_block = BLOCK_SUPERCONTEXT (current_block);
5923 else if (GET_CODE (insn) == CALL_INSN
5924 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5926 rtx cp = PATTERN (insn);
5927 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5929 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5931 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5936 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5937 appears in the block tree, select one of the fragments to become
5938 the new origin block. */
5941 reorder_fix_fragments (block)
5946 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5947 tree new_origin = NULL_TREE;
5951 if (! TREE_ASM_WRITTEN (dup_origin))
5953 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5955 /* Find the first of the remaining fragments. There must
5956 be at least one -- the current block. */
5957 while (! TREE_ASM_WRITTEN (new_origin))
5958 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5959 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5962 else if (! dup_origin)
5965 /* Re-root the rest of the fragments to the new origin. In the
5966 case that DUP_ORIGIN was null, that means BLOCK was the origin
5967 of a chain of fragments and we want to remove those fragments
5968 that didn't make it to the output. */
5971 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5976 if (TREE_ASM_WRITTEN (chain))
5978 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5980 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5982 chain = BLOCK_FRAGMENT_CHAIN (chain);
5987 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5988 block = BLOCK_CHAIN (block);
5992 /* Reverse the order of elements in the chain T of blocks,
5993 and return the new head of the chain (old last element). */
5999 tree prev = 0, decl, next;
6000 for (decl = t; decl; decl = next)
6002 next = BLOCK_CHAIN (decl);
6003 BLOCK_CHAIN (decl) = prev;
6009 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6010 non-NULL, list them all into VECTOR, in a depth-first preorder
6011 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6015 all_blocks (block, vector)
6023 TREE_ASM_WRITTEN (block) = 0;
6025 /* Record this block. */
6027 vector[n_blocks] = block;
6031 /* Record the subblocks, and their subblocks... */
6032 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6033 vector ? vector + n_blocks : 0);
6034 block = BLOCK_CHAIN (block);
6040 /* Return a vector containing all the blocks rooted at BLOCK. The
6041 number of elements in the vector is stored in N_BLOCKS_P. The
6042 vector is dynamically allocated; it is the caller's responsibility
6043 to call `free' on the pointer returned. */
6046 get_block_vector (block, n_blocks_p)
6052 *n_blocks_p = all_blocks (block, NULL);
6053 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6054 all_blocks (block, block_vector);
6056 return block_vector;
6059 static int next_block_index = 2;
6061 /* Set BLOCK_NUMBER for all the blocks in FN. */
6071 /* For SDB and XCOFF debugging output, we start numbering the blocks
6072 from 1 within each function, rather than keeping a running
6074 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6075 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6076 next_block_index = 1;
6079 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6081 /* The top-level BLOCK isn't numbered at all. */
6082 for (i = 1; i < n_blocks; ++i)
6083 /* We number the blocks from two. */
6084 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6086 free (block_vector);
6091 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6094 debug_find_var_in_block_tree (var, block)
6100 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6104 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6106 tree ret = debug_find_var_in_block_tree (var, t);
6114 /* Allocate a function structure and reset its contents to the defaults. */
6117 prepare_function_start ()
6119 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6121 init_stmt_for_function ();
6122 init_eh_for_function ();
6124 cse_not_expected = ! optimize;
6126 /* Caller save not needed yet. */
6127 caller_save_needed = 0;
6129 /* No stack slots have been made yet. */
6130 stack_slot_list = 0;
6132 current_function_has_nonlocal_label = 0;
6133 current_function_has_nonlocal_goto = 0;
6135 /* There is no stack slot for handling nonlocal gotos. */
6136 nonlocal_goto_handler_slots = 0;
6137 nonlocal_goto_stack_level = 0;
6139 /* No labels have been declared for nonlocal use. */
6140 nonlocal_labels = 0;
6141 nonlocal_goto_handler_labels = 0;
6143 /* No function calls so far in this function. */
6144 function_call_count = 0;
6146 /* No parm regs have been allocated.
6147 (This is important for output_inline_function.) */
6148 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6150 /* Initialize the RTL mechanism. */
6153 /* Initialize the queue of pending postincrement and postdecrements,
6154 and some other info in expr.c. */
6157 /* We haven't done register allocation yet. */
6160 init_varasm_status (cfun);
6162 /* Clear out data used for inlining. */
6163 cfun->inlinable = 0;
6164 cfun->original_decl_initial = 0;
6165 cfun->original_arg_vector = 0;
6167 cfun->stack_alignment_needed = STACK_BOUNDARY;
6168 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6170 /* Set if a call to setjmp is seen. */
6171 current_function_calls_setjmp = 0;
6173 /* Set if a call to longjmp is seen. */
6174 current_function_calls_longjmp = 0;
6176 current_function_calls_alloca = 0;
6177 current_function_contains_functions = 0;
6178 current_function_is_leaf = 0;
6179 current_function_nothrow = 0;
6180 current_function_sp_is_unchanging = 0;
6181 current_function_uses_only_leaf_regs = 0;
6182 current_function_has_computed_jump = 0;
6183 current_function_is_thunk = 0;
6185 current_function_returns_pcc_struct = 0;
6186 current_function_returns_struct = 0;
6187 current_function_epilogue_delay_list = 0;
6188 current_function_uses_const_pool = 0;
6189 current_function_uses_pic_offset_table = 0;
6190 current_function_cannot_inline = 0;
6192 /* We have not yet needed to make a label to jump to for tail-recursion. */
6193 tail_recursion_label = 0;
6195 /* We haven't had a need to make a save area for ap yet. */
6196 arg_pointer_save_area = 0;
6198 /* No stack slots allocated yet. */
6201 /* No SAVE_EXPRs in this function yet. */
6204 /* No RTL_EXPRs in this function yet. */
6207 /* Set up to allocate temporaries. */
6210 /* Indicate that we need to distinguish between the return value of the
6211 present function and the return value of a function being called. */
6212 rtx_equal_function_value_matters = 1;
6214 /* Indicate that we have not instantiated virtual registers yet. */
6215 virtuals_instantiated = 0;
6217 /* Indicate that we want CONCATs now. */
6218 generating_concat_p = 1;
6220 /* Indicate we have no need of a frame pointer yet. */
6221 frame_pointer_needed = 0;
6223 /* By default assume not varargs or stdarg. */
6224 current_function_varargs = 0;
6225 current_function_stdarg = 0;
6227 /* We haven't made any trampolines for this function yet. */
6228 trampoline_list = 0;
6230 init_pending_stack_adjust ();
6231 inhibit_defer_pop = 0;
6233 current_function_outgoing_args_size = 0;
6235 if (init_lang_status)
6236 (*init_lang_status) (cfun);
6237 if (init_machine_status)
6238 (*init_machine_status) (cfun);
6241 /* Initialize the rtl expansion mechanism so that we can do simple things
6242 like generate sequences. This is used to provide a context during global
6243 initialization of some passes. */
6245 init_dummy_function_start ()
6247 prepare_function_start ();
6250 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6251 and initialize static variables for generating RTL for the statements
6255 init_function_start (subr, filename, line)
6257 const char *filename;
6260 prepare_function_start ();
6262 current_function_name = (*decl_printable_name) (subr, 2);
6265 /* Nonzero if this is a nested function that uses a static chain. */
6267 current_function_needs_context
6268 = (decl_function_context (current_function_decl) != 0
6269 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6271 /* Within function body, compute a type's size as soon it is laid out. */
6272 immediate_size_expand++;
6274 /* Prevent ever trying to delete the first instruction of a function.
6275 Also tell final how to output a linenum before the function prologue.
6276 Note linenums could be missing, e.g. when compiling a Java .class file. */
6278 emit_line_note (filename, line);
6280 /* Make sure first insn is a note even if we don't want linenums.
6281 This makes sure the first insn will never be deleted.
6282 Also, final expects a note to appear there. */
6283 emit_note (NULL, NOTE_INSN_DELETED);
6285 /* Set flags used by final.c. */
6286 if (aggregate_value_p (DECL_RESULT (subr)))
6288 #ifdef PCC_STATIC_STRUCT_RETURN
6289 current_function_returns_pcc_struct = 1;
6291 current_function_returns_struct = 1;
6294 /* Warn if this value is an aggregate type,
6295 regardless of which calling convention we are using for it. */
6296 if (warn_aggregate_return
6297 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6298 warning ("function returns an aggregate");
6300 current_function_returns_pointer
6301 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6304 /* Make sure all values used by the optimization passes have sane
6307 init_function_for_compilation ()
6311 /* No prologue/epilogue insns yet. */
6312 VARRAY_GROW (prologue, 0);
6313 VARRAY_GROW (epilogue, 0);
6314 VARRAY_GROW (sibcall_epilogue, 0);
6317 /* Indicate that the current function uses extra args
6318 not explicitly mentioned in the argument list in any fashion. */
6323 current_function_varargs = 1;
6326 /* Expand a call to __main at the beginning of a possible main function. */
6328 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6329 #undef HAS_INIT_SECTION
6330 #define HAS_INIT_SECTION
6334 expand_main_function ()
6336 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6337 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6339 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6343 /* Forcibly align the stack. */
6344 #ifdef STACK_GROWS_DOWNWARD
6345 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6346 stack_pointer_rtx, 1, OPTAB_WIDEN);
6348 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6349 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6350 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6351 stack_pointer_rtx, 1, OPTAB_WIDEN);
6353 if (tmp != stack_pointer_rtx)
6354 emit_move_insn (stack_pointer_rtx, tmp);
6356 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6357 tmp = force_reg (Pmode, const0_rtx);
6358 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6359 seq = gen_sequence ();
6362 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6363 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6366 emit_insn_before (seq, tmp);
6372 #ifndef HAS_INIT_SECTION
6373 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6378 extern struct obstack permanent_obstack;
6380 /* The PENDING_SIZES represent the sizes of variable-sized types.
6381 Create RTL for the various sizes now (using temporary variables),
6382 so that we can refer to the sizes from the RTL we are generating
6383 for the current function. The PENDING_SIZES are a TREE_LIST. The
6384 TREE_VALUE of each node is a SAVE_EXPR. */
6387 expand_pending_sizes (pending_sizes)
6392 /* Evaluate now the sizes of any types declared among the arguments. */
6393 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6395 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6396 /* Flush the queue in case this parameter declaration has
6402 /* Start the RTL for a new function, and set variables used for
6404 SUBR is the FUNCTION_DECL node.
6405 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6406 the function's parameters, which must be run at any return statement. */
6409 expand_function_start (subr, parms_have_cleanups)
6411 int parms_have_cleanups;
6414 rtx last_ptr = NULL_RTX;
6416 /* Make sure volatile mem refs aren't considered
6417 valid operands of arithmetic insns. */
6418 init_recog_no_volatile ();
6420 current_function_instrument_entry_exit
6421 = (flag_instrument_function_entry_exit
6422 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6424 current_function_profile
6426 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6428 current_function_limit_stack
6429 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6431 /* If function gets a static chain arg, store it in the stack frame.
6432 Do this first, so it gets the first stack slot offset. */
6433 if (current_function_needs_context)
6435 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6437 /* Delay copying static chain if it is not a register to avoid
6438 conflicts with regs used for parameters. */
6439 if (! SMALL_REGISTER_CLASSES
6440 || GET_CODE (static_chain_incoming_rtx) == REG)
6441 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6444 /* If the parameters of this function need cleaning up, get a label
6445 for the beginning of the code which executes those cleanups. This must
6446 be done before doing anything with return_label. */
6447 if (parms_have_cleanups)
6448 cleanup_label = gen_label_rtx ();
6452 /* Make the label for return statements to jump to. Do not special
6453 case machines with special return instructions -- they will be
6454 handled later during jump, ifcvt, or epilogue creation. */
6455 return_label = gen_label_rtx ();
6457 /* Initialize rtx used to return the value. */
6458 /* Do this before assign_parms so that we copy the struct value address
6459 before any library calls that assign parms might generate. */
6461 /* Decide whether to return the value in memory or in a register. */
6462 if (aggregate_value_p (DECL_RESULT (subr)))
6464 /* Returning something that won't go in a register. */
6465 rtx value_address = 0;
6467 #ifdef PCC_STATIC_STRUCT_RETURN
6468 if (current_function_returns_pcc_struct)
6470 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6471 value_address = assemble_static_space (size);
6476 /* Expect to be passed the address of a place to store the value.
6477 If it is passed as an argument, assign_parms will take care of
6479 if (struct_value_incoming_rtx)
6481 value_address = gen_reg_rtx (Pmode);
6482 emit_move_insn (value_address, struct_value_incoming_rtx);
6487 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6488 set_mem_attributes (x, DECL_RESULT (subr), 1);
6489 SET_DECL_RTL (DECL_RESULT (subr), x);
6492 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6493 /* If return mode is void, this decl rtl should not be used. */
6494 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6497 /* Compute the return values into a pseudo reg, which we will copy
6498 into the true return register after the cleanups are done. */
6500 /* In order to figure out what mode to use for the pseudo, we
6501 figure out what the mode of the eventual return register will
6502 actually be, and use that. */
6504 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6507 /* Structures that are returned in registers are not aggregate_value_p,
6508 so we may see a PARALLEL. Don't play pseudo games with this. */
6509 if (! REG_P (hard_reg))
6510 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6513 /* Create the pseudo. */
6514 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6516 /* Needed because we may need to move this to memory
6517 in case it's a named return value whose address is taken. */
6518 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6522 /* Initialize rtx for parameters and local variables.
6523 In some cases this requires emitting insns. */
6525 assign_parms (subr);
6527 /* Copy the static chain now if it wasn't a register. The delay is to
6528 avoid conflicts with the parameter passing registers. */
6530 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6531 if (GET_CODE (static_chain_incoming_rtx) != REG)
6532 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6534 /* The following was moved from init_function_start.
6535 The move is supposed to make sdb output more accurate. */
6536 /* Indicate the beginning of the function body,
6537 as opposed to parm setup. */
6538 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6540 if (GET_CODE (get_last_insn ()) != NOTE)
6541 emit_note (NULL, NOTE_INSN_DELETED);
6542 parm_birth_insn = get_last_insn ();
6544 context_display = 0;
6545 if (current_function_needs_context)
6547 /* Fetch static chain values for containing functions. */
6548 tem = decl_function_context (current_function_decl);
6549 /* Copy the static chain pointer into a pseudo. If we have
6550 small register classes, copy the value from memory if
6551 static_chain_incoming_rtx is a REG. */
6554 /* If the static chain originally came in a register, put it back
6555 there, then move it out in the next insn. The reason for
6556 this peculiar code is to satisfy function integration. */
6557 if (SMALL_REGISTER_CLASSES
6558 && GET_CODE (static_chain_incoming_rtx) == REG)
6559 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6560 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6565 tree rtlexp = make_node (RTL_EXPR);
6567 RTL_EXPR_RTL (rtlexp) = last_ptr;
6568 context_display = tree_cons (tem, rtlexp, context_display);
6569 tem = decl_function_context (tem);
6572 /* Chain thru stack frames, assuming pointer to next lexical frame
6573 is found at the place we always store it. */
6574 #ifdef FRAME_GROWS_DOWNWARD
6575 last_ptr = plus_constant (last_ptr,
6576 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6578 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6579 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6580 last_ptr = copy_to_reg (last_ptr);
6582 /* If we are not optimizing, ensure that we know that this
6583 piece of context is live over the entire function. */
6585 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6590 if (current_function_instrument_entry_exit)
6592 rtx fun = DECL_RTL (current_function_decl);
6593 if (GET_CODE (fun) == MEM)
6594 fun = XEXP (fun, 0);
6597 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6599 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6601 hard_frame_pointer_rtx),
6606 if (current_function_profile)
6607 PROFILE_HOOK (profile_label_no);
6610 /* After the display initializations is where the tail-recursion label
6611 should go, if we end up needing one. Ensure we have a NOTE here
6612 since some things (like trampolines) get placed before this. */
6613 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6615 /* Evaluate now the sizes of any types declared among the arguments. */
6616 expand_pending_sizes (nreverse (get_pending_sizes ()));
6618 /* Make sure there is a line number after the function entry setup code. */
6619 force_next_line_note ();
6622 /* Undo the effects of init_dummy_function_start. */
6624 expand_dummy_function_end ()
6626 /* End any sequences that failed to be closed due to syntax errors. */
6627 while (in_sequence_p ())
6630 /* Outside function body, can't compute type's actual size
6631 until next function's body starts. */
6633 free_after_parsing (cfun);
6634 free_after_compilation (cfun);
6638 /* Call DOIT for each hard register used as a return value from
6639 the current function. */
6642 diddle_return_value (doit, arg)
6643 void (*doit) PARAMS ((rtx, void *));
6646 rtx outgoing = current_function_return_rtx;
6651 if (GET_CODE (outgoing) == REG)
6652 (*doit) (outgoing, arg);
6653 else if (GET_CODE (outgoing) == PARALLEL)
6657 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6659 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6661 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6668 do_clobber_return_reg (reg, arg)
6670 void *arg ATTRIBUTE_UNUSED;
6672 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6676 clobber_return_register ()
6678 diddle_return_value (do_clobber_return_reg, NULL);
6680 /* In case we do use pseudo to return value, clobber it too. */
6681 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6683 tree decl_result = DECL_RESULT (current_function_decl);
6684 rtx decl_rtl = DECL_RTL (decl_result);
6685 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6687 do_clobber_return_reg (decl_rtl, NULL);
6693 do_use_return_reg (reg, arg)
6695 void *arg ATTRIBUTE_UNUSED;
6697 emit_insn (gen_rtx_USE (VOIDmode, reg));
6701 use_return_register ()
6703 diddle_return_value (do_use_return_reg, NULL);
6706 /* Generate RTL for the end of the current function.
6707 FILENAME and LINE are the current position in the source file.
6709 It is up to language-specific callers to do cleanups for parameters--
6710 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6713 expand_function_end (filename, line, end_bindings)
6714 const char *filename;
6721 #ifdef TRAMPOLINE_TEMPLATE
6722 static rtx initial_trampoline;
6725 finish_expr_for_function ();
6727 /* If arg_pointer_save_area was referenced only from a nested
6728 function, we will not have initialized it yet. Do that now. */
6729 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6730 get_arg_pointer_save_area (cfun);
6732 #ifdef NON_SAVING_SETJMP
6733 /* Don't put any variables in registers if we call setjmp
6734 on a machine that fails to restore the registers. */
6735 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6737 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6738 setjmp_protect (DECL_INITIAL (current_function_decl));
6740 setjmp_protect_args ();
6744 /* Initialize any trampolines required by this function. */
6745 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6747 tree function = TREE_PURPOSE (link);
6748 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6749 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6750 #ifdef TRAMPOLINE_TEMPLATE
6755 #ifdef TRAMPOLINE_TEMPLATE
6756 /* First make sure this compilation has a template for
6757 initializing trampolines. */
6758 if (initial_trampoline == 0)
6761 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6762 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6764 ggc_add_rtx_root (&initial_trampoline, 1);
6768 /* Generate insns to initialize the trampoline. */
6770 tramp = round_trampoline_addr (XEXP (tramp, 0));
6771 #ifdef TRAMPOLINE_TEMPLATE
6772 blktramp = replace_equiv_address (initial_trampoline, tramp);
6773 emit_block_move (blktramp, initial_trampoline,
6774 GEN_INT (TRAMPOLINE_SIZE));
6776 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6780 /* Put those insns at entry to the containing function (this one). */
6781 emit_insns_before (seq, tail_recursion_reentry);
6784 /* If we are doing stack checking and this function makes calls,
6785 do a stack probe at the start of the function to ensure we have enough
6786 space for another stack frame. */
6787 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6791 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6792 if (GET_CODE (insn) == CALL_INSN)
6795 probe_stack_range (STACK_CHECK_PROTECT,
6796 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6799 emit_insns_before (seq, tail_recursion_reentry);
6804 /* Warn about unused parms if extra warnings were specified. */
6805 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6806 warning. WARN_UNUSED_PARAMETER is negative when set by
6808 if (warn_unused_parameter > 0
6809 || (warn_unused_parameter < 0 && extra_warnings))
6813 for (decl = DECL_ARGUMENTS (current_function_decl);
6814 decl; decl = TREE_CHAIN (decl))
6815 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6816 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6817 warning_with_decl (decl, "unused parameter `%s'");
6820 /* Delete handlers for nonlocal gotos if nothing uses them. */
6821 if (nonlocal_goto_handler_slots != 0
6822 && ! current_function_has_nonlocal_label)
6825 /* End any sequences that failed to be closed due to syntax errors. */
6826 while (in_sequence_p ())
6829 /* Outside function body, can't compute type's actual size
6830 until next function's body starts. */
6831 immediate_size_expand--;
6833 clear_pending_stack_adjust ();
6834 do_pending_stack_adjust ();
6836 /* Mark the end of the function body.
6837 If control reaches this insn, the function can drop through
6838 without returning a value. */
6839 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6841 /* Must mark the last line number note in the function, so that the test
6842 coverage code can avoid counting the last line twice. This just tells
6843 the code to ignore the immediately following line note, since there
6844 already exists a copy of this note somewhere above. This line number
6845 note is still needed for debugging though, so we can't delete it. */
6846 if (flag_test_coverage)
6847 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6849 /* Output a linenumber for the end of the function.
6850 SDB depends on this. */
6851 emit_line_note_force (filename, line);
6853 /* Before the return label (if any), clobber the return
6854 registers so that they are not propagated live to the rest of
6855 the function. This can only happen with functions that drop
6856 through; if there had been a return statement, there would
6857 have either been a return rtx, or a jump to the return label.
6859 We delay actual code generation after the current_function_value_rtx
6861 clobber_after = get_last_insn ();
6863 /* Output the label for the actual return from the function,
6864 if one is expected. This happens either because a function epilogue
6865 is used instead of a return instruction, or because a return was done
6866 with a goto in order to run local cleanups, or because of pcc-style
6867 structure returning. */
6869 emit_label (return_label);
6871 /* C++ uses this. */
6873 expand_end_bindings (0, 0, 0);
6875 if (current_function_instrument_entry_exit)
6877 rtx fun = DECL_RTL (current_function_decl);
6878 if (GET_CODE (fun) == MEM)
6879 fun = XEXP (fun, 0);
6882 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6884 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6886 hard_frame_pointer_rtx),
6890 /* Let except.c know where it should emit the call to unregister
6891 the function context for sjlj exceptions. */
6892 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6893 sjlj_emit_function_exit_after (get_last_insn ());
6895 /* If we had calls to alloca, and this machine needs
6896 an accurate stack pointer to exit the function,
6897 insert some code to save and restore the stack pointer. */
6898 #ifdef EXIT_IGNORE_STACK
6899 if (! EXIT_IGNORE_STACK)
6901 if (current_function_calls_alloca)
6905 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6906 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6909 /* If scalar return value was computed in a pseudo-reg, or was a named
6910 return value that got dumped to the stack, copy that to the hard
6912 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6914 tree decl_result = DECL_RESULT (current_function_decl);
6915 rtx decl_rtl = DECL_RTL (decl_result);
6917 if (REG_P (decl_rtl)
6918 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6919 : DECL_REGISTER (decl_result))
6923 #ifdef FUNCTION_OUTGOING_VALUE
6924 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6925 current_function_decl);
6927 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6928 current_function_decl);
6930 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6932 /* If this is a BLKmode structure being returned in registers,
6933 then use the mode computed in expand_return. Note that if
6934 decl_rtl is memory, then its mode may have been changed,
6935 but that current_function_return_rtx has not. */
6936 if (GET_MODE (real_decl_rtl) == BLKmode)
6937 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6939 /* If a named return value dumped decl_return to memory, then
6940 we may need to re-do the PROMOTE_MODE signed/unsigned
6942 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6944 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6946 #ifdef PROMOTE_FUNCTION_RETURN
6947 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6951 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6953 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6954 emit_group_load (real_decl_rtl, decl_rtl,
6955 int_size_in_bytes (TREE_TYPE (decl_result)));
6957 emit_move_insn (real_decl_rtl, decl_rtl);
6959 /* The delay slot scheduler assumes that current_function_return_rtx
6960 holds the hard register containing the return value, not a
6961 temporary pseudo. */
6962 current_function_return_rtx = real_decl_rtl;
6966 /* If returning a structure, arrange to return the address of the value
6967 in a place where debuggers expect to find it.
6969 If returning a structure PCC style,
6970 the caller also depends on this value.
6971 And current_function_returns_pcc_struct is not necessarily set. */
6972 if (current_function_returns_struct
6973 || current_function_returns_pcc_struct)
6976 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6977 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6978 #ifdef FUNCTION_OUTGOING_VALUE
6980 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6981 current_function_decl);
6984 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6987 /* Mark this as a function return value so integrate will delete the
6988 assignment and USE below when inlining this function. */
6989 REG_FUNCTION_VALUE_P (outgoing) = 1;
6991 #ifdef POINTERS_EXTEND_UNSIGNED
6992 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6993 if (GET_MODE (outgoing) != GET_MODE (value_address))
6994 value_address = convert_memory_address (GET_MODE (outgoing),
6998 emit_move_insn (outgoing, value_address);
7000 /* Show return register used to hold result (in this case the address
7002 current_function_return_rtx = outgoing;
7005 /* If this is an implementation of throw, do what's necessary to
7006 communicate between __builtin_eh_return and the epilogue. */
7007 expand_eh_return ();
7009 /* Emit the actual code to clobber return register. */
7014 clobber_return_register ();
7015 seq = gen_sequence ();
7018 after = emit_insn_after (seq, clobber_after);
7020 if (clobber_after != after)
7021 cfun->x_clobber_return_insn = after;
7024 /* ??? This should no longer be necessary since stupid is no longer with
7025 us, but there are some parts of the compiler (eg reload_combine, and
7026 sh mach_dep_reorg) that still try and compute their own lifetime info
7027 instead of using the general framework. */
7028 use_return_register ();
7030 /* Fix up any gotos that jumped out to the outermost
7031 binding level of the function.
7032 Must follow emitting RETURN_LABEL. */
7034 /* If you have any cleanups to do at this point,
7035 and they need to create temporary variables,
7036 then you will lose. */
7037 expand_fixups (get_insns ());
7041 get_arg_pointer_save_area (f)
7044 rtx ret = f->x_arg_pointer_save_area;
7048 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7049 f->x_arg_pointer_save_area = ret;
7052 if (f == cfun && ! f->arg_pointer_save_area_init)
7056 /* Save the arg pointer at the beginning of the function. The
7057 generated stack slot may not be a valid memory address, so we
7058 have to check it and fix it if necessary. */
7060 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7061 seq = gen_sequence ();
7064 push_topmost_sequence ();
7065 emit_insn_after (seq, get_insns ());
7066 pop_topmost_sequence ();
7072 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7073 sequence or a single insn). */
7076 record_insns (insns, vecp)
7080 if (GET_CODE (insns) == SEQUENCE)
7082 int len = XVECLEN (insns, 0);
7083 int i = VARRAY_SIZE (*vecp);
7085 VARRAY_GROW (*vecp, i + len);
7088 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7094 int i = VARRAY_SIZE (*vecp);
7095 VARRAY_GROW (*vecp, i + 1);
7096 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7100 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7103 contains (insn, vec)
7109 if (GET_CODE (insn) == INSN
7110 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7113 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7114 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7115 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7121 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7122 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7129 prologue_epilogue_contains (insn)
7132 if (contains (insn, prologue))
7134 if (contains (insn, epilogue))
7140 sibcall_epilogue_contains (insn)
7143 if (sibcall_epilogue)
7144 return contains (insn, sibcall_epilogue);
7149 /* Insert gen_return at the end of block BB. This also means updating
7150 block_for_insn appropriately. */
7153 emit_return_into_block (bb, line_note)
7159 p = NEXT_INSN (bb->end);
7160 end = emit_jump_insn_after (gen_return (), bb->end);
7162 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7163 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7165 #endif /* HAVE_return */
7167 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7169 /* These functions convert the epilogue into a variant that does not modify the
7170 stack pointer. This is used in cases where a function returns an object
7171 whose size is not known until it is computed. The called function leaves the
7172 object on the stack, leaves the stack depressed, and returns a pointer to
7175 What we need to do is track all modifications and references to the stack
7176 pointer, deleting the modifications and changing the references to point to
7177 the location the stack pointer would have pointed to had the modifications
7180 These functions need to be portable so we need to make as few assumptions
7181 about the epilogue as we can. However, the epilogue basically contains
7182 three things: instructions to reset the stack pointer, instructions to
7183 reload registers, possibly including the frame pointer, and an
7184 instruction to return to the caller.
7186 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7187 We also make no attempt to validate the insns we make since if they are
7188 invalid, we probably can't do anything valid. The intent is that these
7189 routines get "smarter" as more and more machines start to use them and
7190 they try operating on different epilogues.
7192 We use the following structure to track what the part of the epilogue that
7193 we've already processed has done. We keep two copies of the SP equivalence,
7194 one for use during the insn we are processing and one for use in the next
7195 insn. The difference is because one part of a PARALLEL may adjust SP
7196 and the other may use it. */
7200 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7201 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7202 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7203 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7204 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7205 should be set to once we no longer need
7209 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7210 static void emit_equiv_load PARAMS ((struct epi_info *));
7212 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7213 to the stack pointer. Return the new sequence. */
7216 keep_stack_depressed (seq)
7220 struct epi_info info;
7222 /* If the epilogue is just a single instruction, it ust be OK as is. */
7224 if (GET_CODE (seq) != SEQUENCE)
7227 /* Otherwise, start a sequence, initialize the information we have, and
7228 process all the insns we were given. */
7231 info.sp_equiv_reg = stack_pointer_rtx;
7233 info.equiv_reg_src = 0;
7235 for (i = 0; i < XVECLEN (seq, 0); i++)
7237 rtx insn = XVECEXP (seq, 0, i);
7245 /* If this insn references the register that SP is equivalent to and
7246 we have a pending load to that register, we must force out the load
7247 first and then indicate we no longer know what SP's equivalent is. */
7248 if (info.equiv_reg_src != 0
7249 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7251 emit_equiv_load (&info);
7252 info.sp_equiv_reg = 0;
7255 info.new_sp_equiv_reg = info.sp_equiv_reg;
7256 info.new_sp_offset = info.sp_offset;
7258 /* If this is a (RETURN) and the return address is on the stack,
7259 update the address and change to an indirect jump. */
7260 if (GET_CODE (PATTERN (insn)) == RETURN
7261 || (GET_CODE (PATTERN (insn)) == PARALLEL
7262 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7264 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7266 HOST_WIDE_INT offset = 0;
7267 rtx jump_insn, jump_set;
7269 /* If the return address is in a register, we can emit the insn
7270 unchanged. Otherwise, it must be a MEM and we see what the
7271 base register and offset are. In any case, we have to emit any
7272 pending load to the equivalent reg of SP, if any. */
7273 if (GET_CODE (retaddr) == REG)
7275 emit_equiv_load (&info);
7279 else if (GET_CODE (retaddr) == MEM
7280 && GET_CODE (XEXP (retaddr, 0)) == REG)
7281 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7282 else if (GET_CODE (retaddr) == MEM
7283 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7284 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7285 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7287 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7288 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7293 /* If the base of the location containing the return pointer
7294 is SP, we must update it with the replacement address. Otherwise,
7295 just build the necessary MEM. */
7296 retaddr = plus_constant (base, offset);
7297 if (base == stack_pointer_rtx)
7298 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7299 plus_constant (info.sp_equiv_reg,
7302 retaddr = gen_rtx_MEM (Pmode, retaddr);
7304 /* If there is a pending load to the equivalent register for SP
7305 and we reference that register, we must load our address into
7306 a scratch register and then do that load. */
7307 if (info.equiv_reg_src
7308 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7313 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7314 if (HARD_REGNO_MODE_OK (regno, Pmode)
7315 && !fixed_regs[regno]
7316 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7317 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7319 && !refers_to_regno_p (regno,
7320 regno + HARD_REGNO_NREGS (regno,
7322 info.equiv_reg_src, NULL))
7325 if (regno == FIRST_PSEUDO_REGISTER)
7328 reg = gen_rtx_REG (Pmode, regno);
7329 emit_move_insn (reg, retaddr);
7333 emit_equiv_load (&info);
7334 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7336 /* Show the SET in the above insn is a RETURN. */
7337 jump_set = single_set (jump_insn);
7341 SET_IS_RETURN_P (jump_set) = 1;
7344 /* If SP is not mentioned in the pattern and its equivalent register, if
7345 any, is not modified, just emit it. Otherwise, if neither is set,
7346 replace the reference to SP and emit the insn. If none of those are
7347 true, handle each SET individually. */
7348 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7349 && (info.sp_equiv_reg == stack_pointer_rtx
7350 || !reg_set_p (info.sp_equiv_reg, insn)))
7352 else if (! reg_set_p (stack_pointer_rtx, insn)
7353 && (info.sp_equiv_reg == stack_pointer_rtx
7354 || !reg_set_p (info.sp_equiv_reg, insn)))
7356 if (! validate_replace_rtx (stack_pointer_rtx,
7357 plus_constant (info.sp_equiv_reg,
7364 else if (GET_CODE (PATTERN (insn)) == SET)
7365 handle_epilogue_set (PATTERN (insn), &info);
7366 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7368 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7369 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7370 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7375 info.sp_equiv_reg = info.new_sp_equiv_reg;
7376 info.sp_offset = info.new_sp_offset;
7379 seq = gen_sequence ();
7384 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7385 structure that contains information about what we've seen so far. We
7386 process this SET by either updating that data or by emitting one or
7390 handle_epilogue_set (set, p)
7394 /* First handle the case where we are setting SP. Record what it is being
7395 set from. If unknown, abort. */
7396 if (reg_set_p (stack_pointer_rtx, set))
7398 if (SET_DEST (set) != stack_pointer_rtx)
7401 if (GET_CODE (SET_SRC (set)) == PLUS
7402 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7404 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7405 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7408 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7410 /* If we are adjusting SP, we adjust from the old data. */
7411 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7413 p->new_sp_equiv_reg = p->sp_equiv_reg;
7414 p->new_sp_offset += p->sp_offset;
7417 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7423 /* Next handle the case where we are setting SP's equivalent register.
7424 If we already have a value to set it to, abort. We could update, but
7425 there seems little point in handling that case. Note that we have
7426 to allow for the case where we are setting the register set in
7427 the previous part of a PARALLEL inside a single insn. But use the
7428 old offset for any updates within this insn. */
7429 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7431 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7432 || p->equiv_reg_src != 0)
7436 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7437 plus_constant (p->sp_equiv_reg,
7441 /* Otherwise, replace any references to SP in the insn to its new value
7442 and emit the insn. */
7445 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7446 plus_constant (p->sp_equiv_reg,
7448 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7449 plus_constant (p->sp_equiv_reg,
7455 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7461 if (p->equiv_reg_src != 0)
7462 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7464 p->equiv_reg_src = 0;
7468 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7469 this into place with notes indicating where the prologue ends and where
7470 the epilogue begins. Update the basic block information when possible. */
7473 thread_prologue_and_epilogue_insns (f)
7474 rtx f ATTRIBUTE_UNUSED;
7478 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7481 #ifdef HAVE_prologue
7482 rtx prologue_end = NULL_RTX;
7484 #if defined (HAVE_epilogue) || defined(HAVE_return)
7485 rtx epilogue_end = NULL_RTX;
7488 #ifdef HAVE_prologue
7492 seq = gen_prologue ();
7495 /* Retain a map of the prologue insns. */
7496 if (GET_CODE (seq) != SEQUENCE)
7498 record_insns (seq, &prologue);
7499 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7501 seq = gen_sequence ();
7504 /* Can't deal with multiple successors of the entry block
7505 at the moment. Function should always have at least one
7507 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7510 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7515 /* If the exit block has no non-fake predecessors, we don't need
7517 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7518 if ((e->flags & EDGE_FAKE) == 0)
7524 if (optimize && HAVE_return)
7526 /* If we're allowed to generate a simple return instruction,
7527 then by definition we don't need a full epilogue. Examine
7528 the block that falls through to EXIT. If it does not
7529 contain any code, examine its predecessors and try to
7530 emit (conditional) return instructions. */
7536 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7537 if (e->flags & EDGE_FALLTHRU)
7543 /* Verify that there are no active instructions in the last block. */
7545 while (label && GET_CODE (label) != CODE_LABEL)
7547 if (active_insn_p (label))
7549 label = PREV_INSN (label);
7552 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7554 rtx epilogue_line_note = NULL_RTX;
7556 /* Locate the line number associated with the closing brace,
7557 if we can find one. */
7558 for (seq = get_last_insn ();
7559 seq && ! active_insn_p (seq);
7560 seq = PREV_INSN (seq))
7561 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7563 epilogue_line_note = seq;
7567 for (e = last->pred; e; e = e_next)
7569 basic_block bb = e->src;
7572 e_next = e->pred_next;
7573 if (bb == ENTRY_BLOCK_PTR)
7577 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7580 /* If we have an unconditional jump, we can replace that
7581 with a simple return instruction. */
7582 if (simplejump_p (jump))
7584 emit_return_into_block (bb, epilogue_line_note);
7588 /* If we have a conditional jump, we can try to replace
7589 that with a conditional return instruction. */
7590 else if (condjump_p (jump))
7594 ret = SET_SRC (PATTERN (jump));
7595 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7596 loc = &XEXP (ret, 1);
7598 loc = &XEXP (ret, 2);
7599 ret = gen_rtx_RETURN (VOIDmode);
7601 if (! validate_change (jump, loc, ret, 0))
7603 if (JUMP_LABEL (jump))
7604 LABEL_NUSES (JUMP_LABEL (jump))--;
7606 /* If this block has only one successor, it both jumps
7607 and falls through to the fallthru block, so we can't
7609 if (bb->succ->succ_next == NULL)
7615 /* Fix up the CFG for the successful change we just made. */
7616 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7619 /* Emit a return insn for the exit fallthru block. Whether
7620 this is still reachable will be determined later. */
7622 emit_barrier_after (last->end);
7623 emit_return_into_block (last, epilogue_line_note);
7624 epilogue_end = last->end;
7625 last->succ->flags &= ~EDGE_FALLTHRU;
7630 #ifdef HAVE_epilogue
7633 /* Find the edge that falls through to EXIT. Other edges may exist
7634 due to RETURN instructions, but those don't need epilogues.
7635 There really shouldn't be a mixture -- either all should have
7636 been converted or none, however... */
7638 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7639 if (e->flags & EDGE_FALLTHRU)
7645 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7647 seq = gen_epilogue ();
7649 #ifdef INCOMING_RETURN_ADDR_RTX
7650 /* If this function returns with the stack depressed and we can support
7651 it, massage the epilogue to actually do that. */
7652 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7653 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7654 seq = keep_stack_depressed (seq);
7657 emit_jump_insn (seq);
7659 /* Retain a map of the epilogue insns. */
7660 if (GET_CODE (seq) != SEQUENCE)
7662 record_insns (seq, &epilogue);
7664 seq = gen_sequence ();
7667 insert_insn_on_edge (seq, e);
7674 commit_edge_insertions ();
7676 #ifdef HAVE_sibcall_epilogue
7677 /* Emit sibling epilogues before any sibling call sites. */
7678 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7680 basic_block bb = e->src;
7685 if (GET_CODE (insn) != CALL_INSN
7686 || ! SIBLING_CALL_P (insn))
7690 seq = gen_sibcall_epilogue ();
7693 i = PREV_INSN (insn);
7694 newinsn = emit_insn_before (seq, insn);
7696 /* Retain a map of the epilogue insns. Used in life analysis to
7697 avoid getting rid of sibcall epilogue insns. */
7698 record_insns (GET_CODE (seq) == SEQUENCE
7699 ? seq : newinsn, &sibcall_epilogue);
7703 #ifdef HAVE_prologue
7708 /* GDB handles `break f' by setting a breakpoint on the first
7709 line note after the prologue. Which means (1) that if
7710 there are line number notes before where we inserted the
7711 prologue we should move them, and (2) we should generate a
7712 note before the end of the first basic block, if there isn't
7715 ??? This behaviour is completely broken when dealing with
7716 multiple entry functions. We simply place the note always
7717 into first basic block and let alternate entry points
7721 for (insn = prologue_end; insn; insn = prev)
7723 prev = PREV_INSN (insn);
7724 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7726 /* Note that we cannot reorder the first insn in the
7727 chain, since rest_of_compilation relies on that
7728 remaining constant. */
7731 reorder_insns (insn, insn, prologue_end);
7735 /* Find the last line number note in the first block. */
7736 for (insn = BASIC_BLOCK (0)->end;
7737 insn != prologue_end && insn;
7738 insn = PREV_INSN (insn))
7739 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7742 /* If we didn't find one, make a copy of the first line number
7746 for (insn = next_active_insn (prologue_end);
7748 insn = PREV_INSN (insn))
7749 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7751 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7752 NOTE_LINE_NUMBER (insn),
7759 #ifdef HAVE_epilogue
7764 /* Similarly, move any line notes that appear after the epilogue.
7765 There is no need, however, to be quite so anal about the existence
7767 for (insn = epilogue_end; insn; insn = next)
7769 next = NEXT_INSN (insn);
7770 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7771 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7777 /* Reposition the prologue-end and epilogue-begin notes after instruction
7778 scheduling and delayed branch scheduling. */
7781 reposition_prologue_and_epilogue_notes (f)
7782 rtx f ATTRIBUTE_UNUSED;
7784 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7787 if ((len = VARRAY_SIZE (prologue)) > 0)
7791 /* Scan from the beginning until we reach the last prologue insn.
7792 We apparently can't depend on basic_block_{head,end} after
7794 for (insn = f; len && insn; insn = NEXT_INSN (insn))
7796 if (GET_CODE (insn) == NOTE)
7798 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7801 else if ((len -= contains (insn, prologue)) == 0)
7804 /* Find the prologue-end note if we haven't already, and
7805 move it to just after the last prologue insn. */
7808 for (note = insn; (note = NEXT_INSN (note));)
7809 if (GET_CODE (note) == NOTE
7810 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7814 next = NEXT_INSN (note);
7816 /* Whether or not we can depend on BLOCK_HEAD,
7817 attempt to keep it up-to-date. */
7818 if (BLOCK_HEAD (0) == note)
7819 BLOCK_HEAD (0) = next;
7822 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7823 if (GET_CODE (insn) == CODE_LABEL)
7824 insn = NEXT_INSN (insn);
7825 add_insn_after (note, insn);
7830 if ((len = VARRAY_SIZE (epilogue)) > 0)
7834 /* Scan from the end until we reach the first epilogue insn.
7835 We apparently can't depend on basic_block_{head,end} after
7837 for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
7839 if (GET_CODE (insn) == NOTE)
7841 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7844 else if ((len -= contains (insn, epilogue)) == 0)
7846 /* Find the epilogue-begin note if we haven't already, and
7847 move it to just before the first epilogue insn. */
7850 for (note = insn; (note = PREV_INSN (note));)
7851 if (GET_CODE (note) == NOTE
7852 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7856 /* Whether or not we can depend on BLOCK_HEAD,
7857 attempt to keep it up-to-date. */
7859 && BLOCK_HEAD (n_basic_blocks-1) == insn)
7860 BLOCK_HEAD (n_basic_blocks-1) = note;
7863 add_insn_before (note, insn);
7867 #endif /* HAVE_prologue or HAVE_epilogue */
7870 /* Mark P for GC. */
7873 mark_function_status (p)
7876 struct var_refs_queue *q;
7877 struct temp_slot *t;
7884 ggc_mark_rtx (p->arg_offset_rtx);
7886 if (p->x_parm_reg_stack_loc)
7887 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7891 ggc_mark_rtx (p->return_rtx);
7892 ggc_mark_rtx (p->x_cleanup_label);
7893 ggc_mark_rtx (p->x_return_label);
7894 ggc_mark_rtx (p->x_save_expr_regs);
7895 ggc_mark_rtx (p->x_stack_slot_list);
7896 ggc_mark_rtx (p->x_parm_birth_insn);
7897 ggc_mark_rtx (p->x_tail_recursion_label);
7898 ggc_mark_rtx (p->x_tail_recursion_reentry);
7899 ggc_mark_rtx (p->internal_arg_pointer);
7900 ggc_mark_rtx (p->x_arg_pointer_save_area);
7901 ggc_mark_tree (p->x_rtl_expr_chain);
7902 ggc_mark_rtx (p->x_last_parm_insn);
7903 ggc_mark_tree (p->x_context_display);
7904 ggc_mark_tree (p->x_trampoline_list);
7905 ggc_mark_rtx (p->epilogue_delay_list);
7906 ggc_mark_rtx (p->x_clobber_return_insn);
7908 for (t = p->x_temp_slots; t != 0; t = t->next)
7911 ggc_mark_rtx (t->slot);
7912 ggc_mark_rtx (t->address);
7913 ggc_mark_tree (t->rtl_expr);
7914 ggc_mark_tree (t->type);
7917 for (q = p->fixup_var_refs_queue; q != 0; q = q->next)
7920 ggc_mark_rtx (q->modified);
7923 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7924 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7925 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7926 ggc_mark_tree (p->x_nonlocal_labels);
7928 mark_hard_reg_initial_vals (p);
7931 /* Mark the struct function pointed to by *ARG for GC, if it is not
7932 NULL. This is used to mark the current function and the outer
7936 maybe_mark_struct_function (arg)
7939 struct function *f = *(struct function **) arg;
7944 ggc_mark_struct_function (f);
7947 /* Mark a struct function * for GC. This is called from ggc-common.c. */
7950 ggc_mark_struct_function (f)
7954 ggc_mark_tree (f->decl);
7956 mark_function_status (f);
7957 mark_eh_status (f->eh);
7958 mark_stmt_status (f->stmt);
7959 mark_expr_status (f->expr);
7960 mark_emit_status (f->emit);
7961 mark_varasm_status (f->varasm);
7963 if (mark_machine_status)
7964 (*mark_machine_status) (f);
7965 if (mark_lang_status)
7966 (*mark_lang_status) (f);
7968 if (f->original_arg_vector)
7969 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7970 if (f->original_decl_initial)
7971 ggc_mark_tree (f->original_decl_initial);
7973 ggc_mark_struct_function (f->outer);
7976 /* Called once, at initialization, to initialize function.c. */
7979 init_function_once ()
7981 ggc_add_root (&cfun, 1, sizeof cfun, maybe_mark_struct_function);
7982 ggc_add_root (&outer_function_chain, 1, sizeof outer_function_chain,
7983 maybe_mark_struct_function);
7985 VARRAY_INT_INIT (prologue, 0, "prologue");
7986 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7987 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");